IngredientsOleanolic acid (3β-hydroxyolean-12-en-28-oic acid) is a pentacyclic triterpenoid compound with a widespread occurrence throughout the plant kingdom. It is also known by the synonym oleanic acid. Oleanolic acid exists in nature as a free acid or as an aglycone of triterpenoid saponins, and is often ubiquitously found with its isomer, ursolic acid. The molecular formula and weight of OA are C₃₀H₄₈O₃ and 456.70 g/mol, respectively.
Oleanolic acid is characterized by a triterpene skeleton featuring a carboxyl group at C-28 and a hydroxyl group at C-3. It is one of the most common pentacyclic triterpenoid compounds. It is a non-volatile light yellow compound soluble in 1-butanol and ethyl acetate and less soluble in ethanol, 2-propanol, methanol, acetone, and water, where solubility increases with an increase in temperature. In its refined solid state, oleanolic acid forms white needle-like crystals, is odorless and tasteless, is unstable to acid and alkali, and is insoluble in water but soluble in methanol, ethanol, ethyl ether, acetone, and chloroform.
The chemical structure of oleanolic acid has three "active" sites: the C-3 hydroxy group, the C-12 to C-13 double bond, and the C-28 carboxylic acid, which may be chemically modified to change its physical and pharmacological effects.
Triterpenoid oleanolic acid (3β-hydroxy-olea-12-en-28-oic acid) is extracted from more than 1,600 different plants. It serves as a free acid or the aglycone of triterpenoid saponins and is widely distributed in the plant kingdom, particularly in the Oleaceae family. This compound is abundantly present in various edible and medicinal plants, including the leaves, fruits, and epicuticular waxes of olives (Olea europaea), apples (Malus domestica), grapes (Vitis vinifera), and rosemary (Rosmarinus officinalis), with concentrations reported up to 197 mg/kg in virgin olive oil.
It was first studied and isolated from several plants, including Olea europaea (leaves, fruit), Rosa woodsii (leaves), Prosopis glandulosa (leaves and twigs), Phoradendron juniperinum (whole plant), Syzygium claviflorum (leaves), Hyptis capitata (whole plant), Mirabilis jalapa, and Ternstroemia gymnanthera (aerial parts). Other Syzygium species including java apple (Syzygium samarangense) and rose apples contain it, as does Ocimum tenuiflorum (holy basil). Among common dietary sources, oleanolic acid is found in apple, pomegranate, lemon, grapes, pears, and olive.
Additional medicinal plant sources include a very extensive list. Oleanolic acid is also found in Achyranthes aspera, Allium cepa (onion), Allium sativum (garlic), Arctostaphylos uva-ursi, Calendula officinalis, Cornus officinalis, Eriobotrya japonica (loquat), Hedera helix, Ligustrum lucidum, Olea europaea, Panax ginseng, Plantago major, Prunella vulgaris, Psidium guajava (guava), Rosmarinus officinalis, Sambucus nigra, Syzygium aromaticum (clove), Thymus vulgaris, Uncaria tomentosa, Vaccinium corymbosum (blueberry), Vaccinium myrtillus (bilberry), Vitis vinifera, and Zizyphus jujuba, among many others.
Oleanolic acid is extracted from the leaves and fruits of plants of the families Oleaceae, Gentianaceae, Rubiaceae, and Amaranthaceae, among others, and is mainly present in free form and/or in combination with sugars (as saponin glycosides).
The commonly used formulations of OA in the market are tablets, capsules, and pills. Extraction typically involves organic solvents like ethanol (70–95%) or advanced methods such as ultrasound-assisted or microwave-assisted extraction to isolate it from plant matrices like olive pomace. Research formulations have expanded to include self-nanoemulsifying drug delivery systems (SNEDDS), liposomes, nanoparticles, phospholipid complexes, and microemulsions, all aimed at addressing the compound's inherent solubility constraints.
Oleanolic acid biosynthesis starts with mevalonate to create squalene. Squalene monooxygenase in the next step oxidizes squalene and forms an epoxide resulting in 2,3-oxidosqualene. Beta-amyrin synthase creates beta-amyrin by a ring formation cascade. After the formation of beta-amyrin, CYP716AATR2, also known as a cytochrome P450 enzyme, oxidizes carbon 28 turning it into alcohol. CYP716AATR2 converts the alcohol to aldehyde and finally to a carboxylic acid, forming oleanolic acid.
These multifunctional enzymes catalyze a three-step process: initial hydroxylation of the inert methyl group at C-28 to form erythrodiol (28-hydroxy-β-amyrin), followed by oxidation to the corresponding aldehyde (olean-12-en-3β,28-diol-28-al), and finally to the carboxylic acid, yielding oleanolic acid (3β-hydroxyolean-12-en-28-oic acid).
Oleanolic acid has been used in traditional medicine for centuries without any reported severe adverse effects. The compound is integral to a number of ethnopharmacological traditions across the world, though classical texts referred to the plant sources rather than the isolated molecule.
For centuries, natural triterpenoids have been used as antioxidant and anti-inflammatory agents. 3β-hydroxyolean-12-en-28-oic acid, known as oleanolic acid (OA), is a well-characterized triterpenoid present in medicinal plants, fruits, herbs, and olive oil such as Olea europaea, Calendula officinalis, and Viscum album. In the Mediterranean region, the olive plant's leaves and oil have historically been used in folk medicine for skin conditions, digestive complaints, and as antimicrobials, with oleanolic acid now identified as one of the bioactive constituents responsible for these effects.
In Traditional Chinese Medicine, extracts from Ligustrum lucidum (Nu Zhen Zi) and Eriobotrya japonica leaves (bi mei cha) have been used for centuries to "tonify the liver and lung," reduce cough, and clear damp-heat. The fruits of Ligustrum lucidum (glossy privet), the fruits of Forsythia suspensa, and the root of Panax ginseng are classical TCM medicines from which oleanolic acid has been isolated as a principal active marker compound.
Experimental studies have demonstrated that OA has effective liver and kidney protective properties, inhibits platelet aggregation, and has hypolipidemic, hypoglycemic, anti-inflammatory, anti-cancer, anti-stress, anti-ulcer, and anti-microbial properties. OA is used to treat acute jaundice, chronic poisoning hepatitis, liver fibrosis, and cirrhosis.
Oleanolic acid was approved in China for liver diseases in the 1980s, after the beneficial effects of OA against CCl₄-induced acute and chronic liver cirrhosis in laboratory animals were reported. In China, oleanolic acid is used as an OTC drug for oral delivery to treat human liver diseases, such as acute and chronic hepatitis. OA has been used in Chinese medicine to treat liver disorders for over 20 years.
Oleanolic acid, a pentacyclic triterpenoid ubiquitously present in the plant kingdom, receives outstanding attention from the scientific community due to its biological activity against multiple diseases. Oleanolic acid is endowed with a wide range of biological activities with therapeutic potential by means of complex and multifactorial mechanisms.
The mechanism of the antioxidant action of OA is exerted by OA modulating key signaling pathways related to the antioxidant and inflammatory response, such as the Nrf2 pathway, which activates genes responsible for cellular protection against oxidative stress. Oleanolic acid facilitates Nrf2 nuclear accumulation, causing induction of Nrf2-dependent genes, which contributes to protection from hepatotoxicity. Oleanolic acid has Nrf2-dependent and Nrf2-independent effects, both of which likely contribute to oleanolic acid-mediated hepatoprotection.
Oleanolic acid reduces the activation of NF-κB, which is the main regulator of the inflammatory response, leading to a reduction in the level of inflammatory cytokines. Oleanolic acid exhibits high anti-inflammatory activity, inhibiting nitric oxide (NO) and prostaglandin E₂ (PGE₂) production, suppressing NF-κB expression, and activating Nrf2 expression. Oleanolic acid significantly decreases MafK expression and MafK-mediated p65 acetylation, suggesting its potential use in therapeutic applications for the treatment of oxidative stress-induced diseases.
OA was found to enhance insulin sensitivity and glucose uptake, and was found to suppress hepatic glucose production, probably by modulating the IRS/PI3K/Akt/FoxO1 signaling pathway and by mitigating oxidative stress through regulating MAPK pathways. It was demonstrated that OA could improve diabetes by inhibiting the level of α-glucosidase and α-amylase.
Oleanolic acid can reduce lipid accumulation in cells, and can promote nuclear translocation of PPARγ while reducing the expression levels of PPARγ, C/EBP-β, and SREBP-1c. Animal studies have further confirmed the significance of the core target PPARG and the PPAR signaling pathway in OA's anti-obesity effects. Reporter gene assays showed that oleanolic acid increased PPARα activity in keratinocyte cell lines. Punica granatum flower and its component oleanolic acid enhanced the PPARα reporter activity in human embryonic kidney 293 cells, an effect completely suppressed by a selective PPARα antagonist.
Natural and synthetic OA derivatives can modulate multiple signaling pathways including nuclear factor-κB, AKT, signal transducer and activator of transcription 3 (STAT3), mammalian target of rapamycin (mTOR), caspases, intercellular adhesion molecule 1 (ICAM-1), vascular endothelial growth factor (VEGF), and poly (ADP-ribose) polymerase (PARP) in a variety of tumor cells. Oleanolic acid is a potent inhibitor of cellular inflammatory process and a well-known inducer of phase 2 xenobiotic biotransformation enzymes. Main molecular mechanisms underlying anticancer effects of oleanolic acid are mediated by caspases, 5′-adenosine monophosphate-activated protein kinase (AMPK), extracellular signal-regulated kinase 1/2, matrix metalloproteinases (MMPs), pro-apoptotic Bax and Bid, and the PI3K/Akt/mTOR pathway.
TGR5 mRNA is also induced by oleanolic acid; TGR5 is a bile acid-responsive and cell-surface G protein-coupled receptor that, when activated, suppresses macrophage proinflammatory cytokine production, particularly interleukin-1α (IL-1α), IL-1β, and tumor necrosis factor α (TNFα). OA has been shown to activate the Takeda G-protein-coupled receptor (TGR5).
The mechanism of acetylcholinesterase (AChE) inhibitory potential of OA has been investigated using molecular dynamic simulations and docking, as well as in vitro SH-SY5Y human neuroblastoma cells and an in vivo zebrafish model. The inhibitory potential towards the AChE enzyme was examined with an IC₅₀ value of 9.22 μM.
Evidence level: Moderate (extensive preclinical; limited human data; regulatory approval in China).
OA is effective in protecting against various hepatotoxicants, and one of the protective mechanisms is reprogramming the liver to activate the nuclear factor erythroid 2-related factor 2 (Nrf2). The spectrum of OA protection now extends from acute liver injury to chronic fibrosis and cirrhosis, from ischemia-reperfusion injury to immune-modulated liver damage, from ethanol to anti-tuberculosis drug toxicity, and from mushroom toxin phalloidin to bile-duct ligation and bile acid-induced cholestasis.
Oleanolic acid has been reported to exhibit potent hepatoprotective activity. It decreases CCl₄-induced liver parenchymal cell necrosis, steatosis, and degeneration, as well as alcohol-induced chronic cirrhosis. It is marketed in China for human hepatitis.
Animal study details: Rats were given OA 20 mg/kg subcutaneously; BALB/c mice given rifampicin (10 mg/kg), isoniazid (10 mg/kg), and pyrazinamide (30 mg/kg) for 11 weeks to produce liver injury showed that co-administration of an OA/ursolic acid mixture at low doses (4–8 mg/kg, sc) for 11 weeks significantly decreased serum enzyme activities and ameliorated histopathological lesions produced by anti-TB drugs.
In a preclinical study using mice, pharmacological activation of Nrf2 with oleanolic acid (22.5 mg/kg, sc for 4 days) was used. Mice were given phalloidin (1.5 mg/kg, ip for 8 hours) to examine liver injury. Phalloidin increased serum enzyme activities and caused extensive hepatic hemorrhage and necrosis in Nrf2-null and wild-type mice, but less injury was seen in Nrf2-activated mice and OA-pretreated mice.
Human clinical evidence is limited. While oleanolic acid has OTC regulatory status for liver disease in China, robust randomized controlled trials in humans are not yet widely available in the peer-reviewed literature assessed here.
Evidence level: Preliminary (predominantly animal studies; one human clinical trial identified in systematic reviews).
There is evidence suggesting that oleanolic acid might be effective against dyslipidemia, diabetes, and metabolic syndrome, through enhancing insulin response, preserving the functionality and survival of β-cells, and protecting against diabetes complications.
A 2019 systematic review covering databases from 2013–2019 identified the breadth of available evidence: both animal studies (n = 23) and human clinical trials (n = 1) were included in the review to assess the effects of OA formulations on parameters concerning insulin resistance and the MetS components. The methodological quality assessment was performed using SYRCLE's Risk of Bias for animal studies and the Jadad scale. According to the studies in the review, OA improves blood pressure levels, hypertriglyceridemia, hyperglycemia, oxidative stress, and insulin resistance.
A subsequent 2022 systematic review on insulin resistance identified: the bibliographic search was carried out on PubMed, Web of Science, Scopus, Cochrane, and CINAHL databases between January 2001 and May 2022. The electronic search produced 5,034 articles but, after applying inclusion criteria, 13 animal studies and 3 cell experiments were identified. OA was found to enhance insulin sensitivity and glucose uptake, and was found to suppress hepatic glucose production, probably by modulating the IRS/PI3K/Akt/FoxO1 signaling pathway and by mitigating oxidative stress through regulating MAPK pathways.
Human clinical data: One small-scale clinical trial assessed the hypolipidemic effect of OA. Hyperlipidemic patients were administered OA for four weeks (four tablets at once, three times daily). The results showed that total cholesterol, triglycerides, and HDL-cholesterol levels in the serum decreased significantly. Another clinical study was conducted to assess whether the regular intake of an OA-enriched olive oil is effective in the prevention of diabetes. Prediabetic individuals (176 patients) were randomized to receive 55 mL/day of OA-enriched olive oil (equivalent dose 30 mg OA/day) or the same oil not enriched (control group). The results showed that the intake of OA-enriched olive oil reduces the risk of developing diabetes in prediabetic patients. These human studies are limited in number and scale, and more rigorous RCTs are needed before clinical conclusions can be drawn.
In a rat model of pre-diabetes, pre-diabetes was induced by exposing Sprague Dawley rats to a high-fat, high-carbohydrate diet for 20 weeks. The pre-diabetic rats were then treated with OA (80 mg/kg) or metformin (500 mg/kg) in the presence and absence of dietary interventions for a period of 12 weeks.
Evidence level: Strong preclinical (cell-based and animal); no robust human trials.
Oleanolic acid has shown significant anti-inflammatory activity by inhibiting raw paw edema produced by dextran and by suppressing adjuvant-induced arthritis in rats and mice. The compound and its derivatives display anti-inflammatory activity, which has been investigated across cytotoxic, antitumor, antioxidant, anti-inflammatory, anti-HIV, anticholinesterase, alpha-glucosidase-inhibitory, antimicrobial, hepatoprotective, antipruritic, spasmolytic, anti-angiogenic, antiallergic, antiviral, and immunomodulatory activities.
Evidence level: Preclinical (cell and animal models); no completed human clinical trials for OA itself; synthetic derivatives (e.g., CDDO-Me) are in Phase I trials.
Oleanolic acid is a compound known for its potent antitumor properties and has been the subject of investigations in both cell and animal models. Although OA has good biological activity, its low water solubility and bioavailability limit its therapeutic use, and therefore translating the potential of OA into the clinical oncology setting remains challenging. A systematic review and meta-analysis utilized evidence from animal model studies to gain insights into the antitumor mechanisms of OA.
Oleanolic acid also inhibits tumor initiation and tumor promotion. The effects of OA and derivatives of OA on various cancer types have been investigated; however, breast and hepatocellular malignancies are the most studied cancers.
Synthetic derivatives of OA — 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO) and its C-28 methyl ester (CDDO-Me) and C-28 imidazole (CDDO-Im) — have demonstrated potent antiangiogenic and antitumor activities in rodent cancer models. These agents have been under evaluation in Phase I studies in cancer patients. The parent compound OA itself has not yet progressed to completed Phase II/III clinical trials for oncology.
Evidence level: Preliminary (in vitro and analogue-based; no human trials for OA itself).
Oleanolic acid was found to exhibit weak anti-HIV and weak anti-HCV activities in vitro, but more potent synthetic analogs are being investigated as potential drugs. A review of analogues of oleanolic acid and their selected pathogenic antiviral activities includes HIV, the influenza virus, hepatitis B and C viruses, and herpes viruses. The modification of the hydroxyl and carboxylic acid functional groups on OA has resulted in potent compounds with antiviral activity. The anti-HIV activity of synthesized compounds operates via inhibition of HIV-1 replication. The compounds synthesized also hindered virus entry by inhibiting the binding of influenza virus hemagglutinin protein to host cells.
Evidence level: Preliminary (in vitro; no human trials).
Oleanolic acid and ursolic acid have displayed incontestable biological activity, including antibacterial, antiviral, and antiprotozoal effects. The modification of oleanolic acid also resulted in potent antibacterial agents. OA and its acylated analogues were screened for antimicrobial activity against five fungal plant pathogens, and two Gram-positive and two Gram-negative bacteria. Evidence is confined to in vitro models and animal studies; no human clinical trials specifically on OA's antimicrobial effects in infections have been identified.
Evidence level: Emerging preclinical evidence; no human trials completed.
Oleanolic acid is a common pentacyclic triterpenoid that is widely available in nature and has been shown to have protective effects in kidney disease. However, comprehensive studies on its role in kidney diseases are still lacking. Relevant effects include anti-inflammatory, immunomodulatory, anti-oxidative stress, autophagy-enhancing, and antifibrotic effects in renal diseases.
Evidence level: Early/preliminary (cell models, animal models, and computational studies; no human trials).
Studies confirm neuroprotective pharmacological properties of this compound. Oleanolic acid is studied for both its neuroprotective properties. The mechanism of acetylcholinesterase (AChE) inhibitory potential of OA has been investigated using molecular dynamic simulations and docking. Research in animal models of cerebral ischemia and neurodegeneration shows promising signals, but human data are absent.
Evidence level: Preclinical evidence strong; one small human clinical trial on dyslipidemia; larger RCTs lacking.
OA has specific advantages in the treatment of metabolic syndrome and cardiovascular diseases. OA achieves therapeutic effects through a variety of pathways, attracting great interest in the treatment of these conditions. The hypolipidemic effect was evaluated in one small-scale human clinical trial (see Section 5.2 above), showing significant changes in serum lipid profiles. Preclinical work demonstrates reduction of fat accumulation and inflammatory markers, but the clinical evidence base remains thin.
Evidence level: Preclinical (animal models); no human trials.
Results of in vivo experiments indicated that dietary intervention with oleanolic acid can effectively improve fat accumulation in liver tissue and attenuate the levels of IL-6 and TNF-α in serum caused by a high-fat diet. Oleanolic acid did not cause lesions in vital organs at the experimental concentrations. Computer simulation indicated that oleanolic acid could directly bind to PPARγ with a reasonable and stable docking conformation.
Oleanolic acid is a typical BCS Class IV drug with low water-solubility and poor permeability, metabolized by cytochrome P450 (CYP) isozymes in the intestinal tract, such as CYP3A. According to the Biopharmaceutical Classification System (BCS), OA is categorized as a BCS Class IV drug characterized by exceedingly low aqueous solubility and suboptimal intestinal permeability, which collectively constrain its absorption and bioavailability.
Being hydrophobic (logP = 6.32, pKa = 5.11), oleanolic acid exhibits poor aqueous solubility. During in vitro dissolution study, less than 1 μg/ml oleanolic acid was dissolved from raw solid form into an aqueous buffer (pH 1 or 7) after 2 hours. In a human pharmacokinetic study, Tmax was reported to be 5.2 hours after oral administration of an oleanolic acid capsule, indicating delayed in vivo absorption. The absolute oral bioavailability of oleanolic acid was only 0.7% for oral doses of 25 and 50 mg/kg in rat.
A major barrier to translation is OA's suboptimal druggability. OA exhibits poor aqueous solubility and limited oral bioavailability, and its extensive metabolism may further reduce effective systemic exposure, making it difficult to establish consistent exposure-response relationships in vivo.
Oleanolic acid also serves as a framework for the development of novel semi-synthetic triterpenoids that could prove vital in finding therapeutic modalities for various ailments. There are recent advances in the design and synthesis of chemical derivatives of OA to enhance its solubility, bioavailability, and potency. Recently, nanoparticulate drug delivery systems have been developed, which may help generate useful formulations of OA for clinical applications. Nanoparticulate drug delivery systems enhance the dissolution rate and bioavailability of OA, providing a feasible formulation method for clinical use.
Oleanolic acid has been successfully used as an OTC oral drug to treat human liver disorders in China due to its hepatoprotective effect. In addition, it exerts anti-inflammatory, antitumor, and anti-hyperlipidemic effects.
No standardized human dosage has been established by major international regulatory agencies (e.g., NIH, EMA, WHO) for oleanolic acid as a dietary supplement. Dosages in published human trials are sparse, and inter-study comparisons are complicated by differences in formulation, vehicle, and route of administration.
Oleanolic acid has GRAS (Generally Recognized as Safe) status from the FDA, and it is non-toxic, with low toxicity reported in animal studies. It has been used in traditional medicine for centuries without any reported severe adverse effects.
In vivo animal experiments indicated that dietary intervention with oleanolic acid can effectively improve fat accumulation in liver tissue; oleanolic acid did not cause lesions in vital organs at the experimental concentrations.
High doses of oleanolic acid may cause mild adverse effects such as gastrointestinal discomfort, nausea, diarrhea, and hepatotoxicity. Notably, the same compound that is hepatoprotective at low-to-moderate doses may become hepatotoxic at high doses. This has been documented in scientific literature, with researchers noting a biphasic effect that is dependent on the dose used.
Oleanolic acid may also cause a drop in blood pressure and blood glucose levels, which could be problematic for people taking medication for hypertension or diabetes.
Oleanolic acid may lower blood pressure, so it could enhance the effects of medications used to treat hypertension, such as angiotensin-converting enzyme (ACE) inhibitors and calcium channel blockers.
Oleanolic acid may enhance the immunosuppressive effects of medications used to treat autoimmune disorders or prevent organ rejection after transplant surgery.
Oleanolic acid is metabolized by cytochrome P450 (CYP) isozymes in the intestinal tract, such as CYP3A. These are reasons for the low oral bioavailability of OA which have restricted its wide application. Because CYP3A is the primary metabolic enzyme involved, interactions with other CYP3A substrates, inhibitors, or inducers are theoretically possible, though specific documented human drug interaction studies are limited in the peer-reviewed literature reviewed here.
Pharmacokinetic limitations remain a central obstacle, including poor aqueous solubility, variable absorption, extensive first-pass metabolism, uncertain tumor exposure, and limited PK/PD linkage. Derivatization and nanocarriers may introduce new uncertainties related to metabolic fate, drug-drug interactions, off-target accumulation, manufacturability, and long-term safety.
Across the field, conclusions are additionally constrained by model heterogeneity, incomplete subtype coverage, limited normal-cell controls, and insufficient mechanistic causality testing. Overall, oleanolic acid and its derivatives should be viewed as preclinical leads with potential relevance. The majority of scientific investigations have been conducted in cell-culture models and animal models. Both animal studies (n = 23) and human clinical trials (n = 1) were included in a comprehensive 2019 systematic review covering six years of literature, reflecting the relative scarcity of human data. Future well-designed, adequately powered randomized controlled trials in human populations are necessary to establish efficacy and safety parameters for OA as a dietary supplement or pharmaceutical agent.
Health conditions that Oleanolic acid may help support.
OA is a potent natural antioxidant that neutralizes reactive oxygen species, inhibits lipid peroxidation, and upregulates endogenous antioxidant enzymes (SOD, GPx, catalase) via Nrf2 pathway activation. These mechanisms have been confirmed in multiple in vitro and in vivo experimental models.
OA inhibits atherosclerosis development in multiple animal models, reducing lipid plaque accumulation, lowering LDL-C, and inducing vasorelaxation via endothelium-dependent NO release. It may also protect arterial walls through FXR-mediated angiotensin-(1-7) upregulation.
OA reduces synovial inflammation in osteoarthritis models by suppressing IL-1β-induced fibroblast-like synoviocyte dysfunction via the SIRT3-NF-κB axis. It inhibits COX-2, PGE2, iNOS, and matrix metalloproteinases in joint tissue. Traditional Chinese medicine also uses OA-containing plants for joint complaints.
OA exhibits antihypertensive activity in animal models through diuretic/natriuretic mechanisms, direct heart rate reduction, and downregulation of sPLA2 and fatty acid synthase. In Dahl salt-sensitive hypertensive rats, OA prevented the development of severe hypertension over 6 weeks.
Oleanolic acid (OA) reduces hyperglycemia in animal models by suppressing hepatic gluconeogenesis via the Akt/FoxO1 axis and inhibiting alpha-glucosidase. It enhances insulin sensitivity and supports pancreatic beta-cell function. A 2022 systematic review confirmed these mechanisms across 13 animal studies and 3 cell experiments, though human RCTs remain scarce.
OA exerts osteoprotective effects in ovariectomized mice and aged female rats, significantly increasing bone mineral density, improving bone microarchitecture, enhancing calcium balance, and modulating vitamin D metabolism via renal CYP27B1 upregulation.
OA has documented antifungal activity including against Candida species in preclinical studies, and is listed in multiple pharmacological reviews as having antimicrobial and antifungal properties. This activity is noted alongside its antibacterial and antiparasitic effects.
OA lowers total cholesterol and LDL-cholesterol and raises HDL-cholesterol in multiple animal models of hyperlipidemia and atherosclerosis, with effects comparable to atorvastatin in some atherosclerosis models. These lipid-modulating effects are mediated partly through PPARγ, AdipoR1/R2 pathways.
OA is a well-documented natural anti-inflammatory agent. It inhibits NF-κB, COX-2, and iNOS, suppresses pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), and reduces endothelial cell adhesion molecule expression. Anti-inflammatory effects have been reproduced across numerous in vitro and animal models.
OA exhibits analgesic activity in standard animal pain models, including acetic-acid-induced writhing and carrageenan-induced inflammation. Its anti-nociceptive effects are mediated partly through COX inhibition and NF-κB suppression, consistent with its broader anti-inflammatory profile.
OA protects against neuroinflammation-driven neurotoxicity and reverses scopolamine-induced memory impairment in rodents via TrkB/BDNF-ERK1/2-CREB pathway activation. It also reduces Alzheimer's-related amyloid-beta-driven astrocyte toxicity and cognitive decline markers.
OA ameliorates dextran sodium sulfate (DSS)-induced colitis in mice by restoring Th17/Treg balance, inhibiting NF-κB, preserving intestinal tight junction proteins (ZO-1, occludin), and reducing inflammatory cytokines. Multiple independent murine studies confirm these effects.
OA alleviates atopic dermatitis (eczema)-like symptoms in a DNCB-induced mouse model by suppressing Th2 cytokines, reducing serum histamine, and blocking Akt/NF-κB/STAT1 activation in keratinocytes. Both topical and oral routes have shown efficacy in animal models.
OA has preclinically demonstrated antifungal activity relevant to skin fungal infections, including against dermatophytes, as part of its broader antimicrobial activity profile. This is supported by in vitro and limited animal evidence.
OA's anti-inflammatory mechanisms (NF-κB inhibition, COX-2 suppression, tight junction restoration) are directly relevant to gastritis pathophysiology. It reduces gastric mucosal inflammatory markers in preclinical models, supported by multiple mechanistic studies.
OA exerts multiple biological activities relevant to healthy aging including antioxidant defense, anti-inflammation, hepatoprotection, neuroprotection, bone preservation, and metabolic regulation. A 2025 PMC review confirmed OA's role as a natural antioxidant against oxidative stress underlying cancer, cardiovascular, and neurodegenerative aging-related diseases.
OA reduces fat accumulation and attenuates obesity in high-fat-diet animal models, partly by modulating lipid metabolism via PPARγ and inhibiting adipogenesis. In HFD-fed mice, OA treatment suppressed increases in fat mass and body weight.
OA protects the heart from hyperglycemia-induced contractile dysfunction, ischemia-reperfusion injury, and oxidative damage in cardiac myoblasts and isolated rat hearts. It reduces cardiac apoptosis and oxidative stress and has been described as a novel cardioprotective triterpenoid.
OA shows potent antiviral activity specifically against HSV-1 in cell-based and animal studies, including against acyclovir-resistant strains. It suppresses viral replication by downregulating the helicase-primase complex (UL5, UL8, UL52) and reduces skin lesions in vivo.
OA reduces intestinal inflammation and restores mucosal barrier integrity in DSS-induced colitis models by rebalancing Th17/Treg cells, suppressing NF-κB, and upregulating tight junction proteins. These findings are consistent across several independent studies.
OA enhances insulin sensitivity and suppresses hepatic glucose production in animal models via modulation of the IRS-1/PI3K/Akt/FoxO1 pathway. A 2022 systematic review confirmed these molecular targets across 13 animal studies, though human RCTs are still needed.
OA protects against renal fibrosis, oxidative kidney damage, and diabetic nephropathy in multiple animal models. Mechanisms include Nrf2-mediated antioxidant enhancement, TGF-β/Smad pathway inhibition, and suppression of inflammatory cell infiltration. Protection against renal oxidative stress is also documented in diet-induced prediabetes models.
OA has well-established hepatoprotective effects demonstrated in multiple animal models and acknowledged in Chinese pharmacopeia, where it is listed as a liver-protective drug. It reduces liver enzyme elevations, enhances antioxidant enzyme systems (SOD, GPx), and suppresses inflammation via PPARα and NF-κB pathways. Limited human data suggest potential benefit in hepatitis and liver fibrosis.
OA addresses multiple components of metabolic syndrome simultaneously—hyperglycemia, dyslipidemia, hypertension, and obesity—making it a candidate treatment agent according to a 2019 systematic review. A human crossover study with olive oil triterpenoids (including OA) reported reductions in DNA oxidation and plasma inflammatory biomarkers.
OA demonstrates consistent bone-protective effects in ovariectomized and aged animal models by increasing bone mineral density, improving bone microarchitecture, modulating calcium homeostasis, and activating vitamin D synthesis enzymes. It is considered a candidate for postmenopausal osteoporosis prevention.
OA has antioxidant and anti-inflammatory properties relevant to skin aging, inhibits 5-alpha-reductase in skin, modulates collagen synthesis, and improves skin barrier function. Preclinical studies show effects on fibroblast biology and sebum regulation relevant to skin aging.
OA consistently reduces triglyceride levels in animal models of hyperlipidemia, metabolic syndrome, and atherosclerosis. Effects occur alongside reductions in total cholesterol and LDL, and appear mediated through PPARγ and lipase activity modulation.
OA has demonstrated gastric and intestinal ulcer-healing properties in preclinical models, including promoting wound re-epithelialization and reducing ulceration. Use of OA as part of multi-component preparations in human wounds has also shown healing benefits.
OA demonstrates antiviral activity in preclinical studies against HSV-1 (including acyclovir-resistant strains), HIV, influenza, and hepatitis B/C viruses. Its anti-HSV-1 mechanism involves disruption of the viral helicase-primase complex (UL8), blocking replication at the immediate early stage of infection.
OA promotes wound healing by stimulating cell migration via EGF receptor and MAP kinase activation, increasing wound tensile strength in animals, and modulating collagen production. Use of OA-containing mixtures in human wounds has shown accelerated healing and improved aesthetic outcomes in at least one study.
Body systems that Oleanolic acid may help support.
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