Aneurisma

Astaxanthin is a marine xanthophyll carotenoid with potent antioxidant activity that reduces oxidative stress-mediated chondrocyte damage in OA. In vitro and animal studies demonstrate astaxanthin suppresses IL-1β–induced MMP expression and NF-κB signaling in chondrocytes. An open-label pilot study in OA patients found 12 mg/day astaxanthin for 8 weeks significantly improved VAS pain scores and WOMAC function.

Avian (chicken sternal) cartilage is the primary commercial source of undenatured type II collagen (UC-II), chondroitin sulfate, and hyaluronic acid. UC-II at 40 mg/day induces oral tolerance via gut-associated lymphoid tissue, reducing T-cell–mediated degradation of articular cartilage. A double-blind RCT (Crowley et al., 2009, n=52 knee OA) found UC-II from avian cartilage superior to glucosamine+chondroitin on all three WOMAC subscales at 90 days. A 2022 systematic review confirmed type II collagen peptides as consistently efficacious across multiple OA trials.

Bovine collagen peptides supply glycine, proline, and hydroxyproline to support cartilage extracellular matrix turnover. Multiple RCTs and a meta-analysis show bovine collagen peptides reduce joint pain and may support cartilage structure in osteoarthritis.

Boron is a trace mineral that influences cartilage health through regulation of vitamin D, calcium, and magnesium metabolism, and direct stimulation of chondrocyte extracellular matrix synthesis. Epidemiological data show lower OA incidence in populations with higher boron intake. A small double-blind clinical trial found boron supplementation (6 mg/day) significantly reduced OA symptoms versus placebo.

Boswellia serrata gum resin contains boswellic acids that inhibit 5-lipoxygenase and NF-κB pathways central to cartilage inflammation and matrix degradation. A 2025 randomized, double-blind, multicenter, placebo-controlled trial in 62 knee OA patients showed Boswellia serrata extract significantly reduced pain, stiffness, cartilage degeneration biomarkers (CTX-II, COMP, MMP-3), and inflammatory markers over 90 days. Multiple systematic reviews and a 2022 network meta-analysis support Boswellia among leading OA nutraceuticals.

Boswellic acids are the active pentacyclic triterpenoid constituents of Boswellia serrata resin, primarily inhibiting 5-lipoxygenase and NF-κB pathways central to cartilage inflammation. Clinical trials using standardized Boswellia extracts defined by boswellic acid content have demonstrated reductions in OA pain, stiffness, and cartilage degradation biomarkers including CTX-II, COMP, and MMP-3. They are the pharmacologically active fraction driving Boswellia's evidence-based OA effects.

Cetylated fatty acids (CEF) are fatty acid esters of cetyl alcohol, primarily cetyl myristoleate, proposed to lubricate joint membranes and modulate immune responses in OA. A double-blind RCT (Hesslink et al., J Rheumatol 2002, n=64 knee OA patients, 30 days) found oral/topical CEF significantly improved WOMAC scores and knee range of motion versus placebo. A second RCT (Kraemer et al. 2004, n=40) confirmed significant reductions in knee OA symptoms and improved function.

Chondroitin is a structural glycosaminoglycan component of articular cartilage that provides elasticity by retaining water and resisting compressive loads. It has been tested in over 22 RCTs for osteoarthritis; laboratory studies show it reduces enzymes that break down cartilage collagen. A 2016 MOVES trial found glucosamine and chondroitin combined was as effective as celecoxib for knee OA pain. Pharmacologic-grade preparations may have clinically significant chondroprotective benefits.

Cissus quadrangularis is an Ayurvedic and African medicinal plant used traditionally for fractures and joint pain. It contains phytosterols, triterpenoids, and high-dose ascorbic acid that promote collagen synthesis and cartilage integrity. A double-blind RCT (Oben et al. 2008, n=72, 8 weeks) found Cissus quadrangularis extract significantly reduced knee OA pain, stiffness, and functional limitations on WOMAC versus placebo. Ayurvedic pharmacopoeia lists it as a first-line herb for bone and joint disorders.

EPA and DHA from cod liver oil suppress matrix metalloproteinases (MMPs) and aggrecanases that degrade cartilage in inflammatory arthritis. Clinical studies in RA show reduced joint damage biomarkers with CLO supplementation. Omega-3s reduce IL-1β-driven chondrocyte apoptosis in vitro.

Collagen is the primary structural protein of articular cartilage. Both hydrolyzed collagen and undenatured type II collagen have been studied in clinical trials for OA. Hydrolyzed collagen is absorbed and incorporated into joint cartilage with clinical evidence of improved mobility and pain. Undenatured type II collagen induces oral tolerance via gut-associated lymphoid tissue, reducing autoimmune-like cartilage degradation. Multiple systematic reviews support its role in cartilage repair.

Bovine colostrum is rich in IGF-1, TGF-β, and lactoferrin—growth factors and proteins that directly stimulate chondrocyte proliferation, type II collagen synthesis, and cartilage matrix repair. A clinical study (Thijssen et al., 2016, n=51 adults) found bovine colostrum significantly reduced exercise-induced joint pain versus placebo. Lactoferrin from colostrum inhibits IL-1β–induced MMP production in chondrocytes, providing direct chondroprotective activity.

Copper is an essential trace mineral and cofactor for lysyl oxidase, the enzyme that catalyzes the cross-linking of collagen and elastin in articular cartilage and connective tissue. Copper deficiency impairs cartilage collagen cross-linking and mechanical integrity. Copper-dependent superoxide dismutase (CuZnSOD) protects chondrocytes from oxidative damage. Copper is included in evidence-based joint supplement formulas supporting cartilage collagen quality.

Curcumin is the primary bioactive polyphenol of turmeric, inhibiting NF-κB, COX-2, 5-LOX, and inflammatory cytokines (IL-1β, TNF-α, MMPs) that drive cartilage degradation. A landmark comparative RCT (Kuptniratsaikul et al. 2014, n=367 knee OA patients) found curcumin extract as effective as ibuprofen 1200 mg/day for knee pain relief with better GI tolerability. A 2021 meta-analysis of 10 RCTs confirmed curcuminoids significantly reduced WOMAC pain and stiffness, and ESCEO guidelines recognize curcuminoids as an OA nutraceutical.

Curcuminoids are the polyphenolic complex of Curcuma longa including curcumin, demethoxycurcumin, and bisdemethoxycurcumin. They collectively inhibit NF-κB, COX-2, 5-LOX, and MMP pathways involved in cartilage degradation. A 2021 meta-analysis of 10 RCTs confirmed significant reduction of WOMAC pain and stiffness in knee OA, and ESCEO guidelines list curcuminoids as a recognized OA nutraceutical option.

Devil's Claw (Harpagophytum procumbens) is a southern African medicinal plant whose secondary tuber roots contain harpagoside and other iridoid glycosides with anti-inflammatory, analgesic, and chondroprotective activities. In vitro data show devil's claw extract increases hyaluronic acid synthesis in chondrocytes by 41% and GAG levels by 38%. Multiple RCTs and systematic reviews support efficacy for OA and musculoskeletal pain, and German Commission E and ESCOP have approved it for joint and musculoskeletal conditions.

Rosa canina rosehip preparations have demonstrated chondroprotective mechanisms in vitro and in vivo, with clinical evidence showing protection of articular cartilage via suppression of IL-1β-induced NF-κB activation in chondrocytes and inhibition of pro-inflammatory metalloproteases. These effects are linked to improved joint outcomes in OA clinical trials.

Eggshell membrane is a concentrated source of native type I and V collagen, glycosaminoglycans (hyaluronic acid, chondroitin sulfate), elastin, and lysyl oxidase relevant to cartilage matrix support. Two double-blind RCTs of natural eggshell membrane (NEM) supplementation (Ruff et al., 2009) demonstrated significant improvements in OA joint pain and function. A 2022 network meta-analysis specifically included eggshell membrane among supplements supporting cartilage repair and maintenance.

Ginger (Zingiber officinale) contains gingerols and shogaols that inhibit COX-1, COX-2, and 5-LOX enzymes, reducing inflammatory prostaglandins and leukotrienes involved in cartilage degradation. A meta-analysis of RCTs (Bartels et al., Osteoarthritis Cartilage 2015) found ginger supplementation modestly but significantly reduced OA pain and disability. A 2022 network meta-analysis identified ginger among nutraceuticals with clinical evidence for knee OA.

Glucosamine is a naturally occurring amino monosaccharide essential for synthesis of cartilage matrix glycosaminoglycans and proteoglycans. Two pivotal 3-year RCTs of glucosamine sulfate demonstrated a structure-modifying effect (reduced radiographic joint-space narrowing) in knee OA. EULAR granted glucosamine sulfate its highest evidence level (1A) for knee OA management. A Cochrane review of 25 RCTs supports its symptomatic efficacy, particularly the sulfate form.

Glycine is a rate-limiting substrate for type II collagen (the primary collagen of cartilage) and directly stimulates collagen synthesis by chondrocytes in vitro. Low-molecular-weight collagen peptides enriched in glycine, proline, and hydroxyproline are absorbed systemically and accumulate in joint cartilage. RCTs of collagen peptides show analgesic and functional benefits for osteoarthritis.

Glycosaminoglycans (GAGs) are the primary structural polysaccharides of articular cartilage, including chondroitin sulfate, hyaluronic acid, and keratan sulfate, trapping water to provide compressive resistance. Their loss is the defining biochemical event in OA. Supplemental GAGs (chondroitin sulfate, hyaluronic acid, N-acetylglucosamine) have been validated in clinical trials. A 2022 MDPI nutraceutical review confirmed exogenous GAGs stimulate anabolic cartilage metabolism and delay catabolic cartilage degradation.

Green-lipped mussel (Perna canaliculus) from New Zealand contains novel omega-3 PUFAs (including unique ETA), glycosaminoglycans (chondroitin sulfate, glucosamine), and antioxidants providing anti-inflammatory and chondroprotective properties. A 2021 PLOS ONE study found oral GLM reduced cartilage damage, suppressed MMP-3, MMP-13, ADAMTS5 in OA chondrocytes, and reduced inflammatory biomarkers in a rat OA model. A 2021 systematic review supports its use for OA.

Harpagoside is the primary iridoid glycoside marker compound of Devil's Claw (Harpagophytum procumbens) and its principal pharmacologically active constituent for joint inflammation. Standardized devil's claw extracts normalized to harpagoside content are used in approved preparations for musculoskeletal OA disorders. Clinical doses providing 50–100 mg/day harpagoside have shown superiority to placebo in multiple RCTs and are used in EMA-approved herbal medicine.

Hyaluronic acid (HA) is a non-sulfated glycosaminoglycan and natural component of both articular cartilage and synovial fluid, where it maintains viscoelasticity, lubrication, and shock absorption. It is recognized alongside glucosamine sulfate, chondroitin sulfate, and collagen hydrolysate as an established chondroprotective nutraceutical. Oral HA supplementation has demonstrated joint pain benefits in clinical studies, and a 2022 retrospective RCT combining native type II collagen with HA demonstrated improvements in WOMAC and cartilage degeneration biomarkers.

Boswellia serrata actively protects cartilage matrix by inhibiting enzymes that degrade extracellular matrix proteins (collagenase, elastase, hyaluronidase) and matrix metalloproteinases (MMP-3, MMP-13). Clinical trials in OA show reduced synovial fluid MMP-3 and radiographic evidence of improved knee joint space. AKBA also protects chondrocytes from IL-1β-induced SOX-9 depletion.

Krill oil provides omega-3 fatty acids (EPA and DHA) in phospholipid form with superior bioavailability compared to fish oil, plus the antioxidant astaxanthin. A randomized, double-blind, placebo-controlled trial (Deutsch, J Am Coll Nutr 2007, n=90) found krill oil 300 mg/day for 30 days significantly reduced WOMAC pain, stiffness, and functional impairment scores and serum CRP versus placebo in OA and RA patients. A 2022 network meta-analysis identified krill oil as improving the joint microenvironment in knee OA.

The same randomized clinical trial that assessed bone turnover in menopausal women also measured cartilage degradation marker CTX-II and found a statistically significant reduction with kudzu extract. This represents the first human evidence that kudzu may exert chondroprotective effects, likely through its phytoestrogenic isoflavones.

Glycine constitutes approximately one-third of all amino acid residues in collagen, which forms the structural matrix of cartilage. Adequate glycine is rate-limiting for collagen synthesis, and deficiency impairs maximal collagen production. While most direct evidence comes from biochemical and in vitro work, clinical trials of collagen peptides (which are glycine-rich) support cartilage and joint matrix support.

Cartilage extracellular matrix is predominantly type II collagen, which is rich in proline and hydroxyproline. Low-molecular-weight collagen peptides (LMCPs), abundant in glycine, proline, and hydroxyproline, have been tested in clinical trials for knee osteoarthritis. These peptides stimulate chondrocyte and fibroblast activity and support proteoglycan and hyaluronic acid synthesis. Evidence from RCTs supports their role in reducing joint pain and supporting cartilage structural components.

Manganese is an essential trace mineral and obligate cofactor for glycosyltransferases required for glycosaminoglycan biosynthesis in cartilage proteoglycans and for MnSOD protecting chondrocytes from oxidative damage. Manganese deficiency impairs proteoglycan synthesis and cartilage integrity in animal models. It is a standard component of evidence-based combination cartilage supplements (e.g., Cosamin-DS with glucosamine, chondroitin, and manganese) validated in clinical trials.

Methylcobalamin (vitamin B12, active coenzyme form) is required for methionine synthase activity and methylation reactions supporting connective tissue matrix synthesis. Vitamin B12 deficiency is associated with elevated homocysteine, which directly degrades cartilage through MMP-mediated mechanisms. Clinical studies link homocysteine reduction (via B12/folate) with improved OA and joint outcomes, and methylcobalamin combined with folate has been shown to reduce cartilage degradation biomarkers (CTX-II) in OA patients.

MSM is an organosulfur compound studied for OA and joint pain through anti-inflammatory and antioxidant mechanisms, and provision of sulfur for collagen and GAG synthesis. A double-blind, placebo-controlled pilot trial (Kim et al., 2006, n=50 knee OA patients, 12 weeks) found 6 g/day MSM significantly improved WOMAC pain and physical function scores. A second RCT (Debbi et al., 2011, n=49 knee OA patients) confirmed significant WOMAC and functional improvements.

Research into CMO suggests it may protect joint cartilage through anti-inflammatory mechanisms and joint lubrication, reducing mechanical and inflammatory damage to cartilage. In animal models of collagen-induced arthritis — which involves synovitis and cartilage/bone erosions — CMO treatment reduced both incidence and severity of disease. In vitro studies also indicate potential tissue-protective effects at specific concentrations.

N-Acetyl-Glucosamine (NAG) is the acetylated form of glucosamine and a direct biosynthetic precursor for hyaluronic acid and glycosaminoglycan synthesis in chondrocytes. In vitro evidence confirms direct incorporation into cartilage GAG chains. A 12-week double-blind RCT (Talent & Gracy, 1996, n=31 OA patients) found NAG 3 g/day significantly reduced OA pain and stiffness scores versus placebo, suggesting superior direct utility compared to free glucosamine for GAG synthesis.

Omega-3 polyunsaturated fatty acids (EPA and DHA) inhibit both COX and 5-LOX pathways, reducing prostaglandins and leukotrienes that mediate cartilage-degrading inflammation in OA. A 2011 PMC review identified omega-3 fatty acids alongside glucosamine and chondroitin as validated chondroprotective nutrients with dual anti-inflammatory and anabolic mechanisms. Fish oil RCTs and meta-analyses consistently show reductions in joint pain scores in OA and inflammatory arthritis.

Pycnogenol reduces markers of cartilage degradation such as MMP-3, MMP-13, and IL-1β in patients with severe osteoarthritis. Its polyphenolic constituents distribute into synovial fluid. Multiple RCTs show reduced pain, stiffness, and analgesic use in osteoarthritis patients.

Bromelain is used clinically for osteoarthritis, a condition involving cartilage degradation. Its anti-inflammatory effects reduce cartilage-degrading cytokines (IL-1β, TNF-α), and manganese in pineapple is a cofactor for chondroitin sulfate synthesis. Clinical trials in OA patients show symptomatic improvement.

Proteoglycans (primarily aggrecan) are the major macromolecules of articular cartilage extracellular matrix, where their loss of glycosaminoglycan chains defines OA cartilage degeneration. Serum COMP (a cartilage proteoglycan-associated marker) is a validated cartilage biomarker reduced by OA nutraceuticals including Boswellia and collagen in RCTs. Exogenous GAG/proteoglycan precursors (glucosamine, chondroitin, N-acetyl-glucosamine) directly support proteoglycan biosynthesis in chondrocytes.

Pycnogenol (French maritime pine bark extract) is a standardized extract containing proanthocyanidins with anti-inflammatory, antioxidant, and chondroprotective activities. Two randomized clinical trials found Pycnogenol supplementation significantly reduced OA pain, stiffness, and requirement for NSAIDs versus placebo. A 2008 RCT demonstrated Pycnogenol reduced serum inflammatory biomarkers and improved WOMAC scores in 100 knee OA patients.

Quercetin is a flavonol that inhibits NF-κB, COX-2, and multiple inflammatory mediators implicated in cartilage degradation. Multiple in vitro studies confirm quercetin reduces IL-1β–induced MMP expression and chondrocyte apoptosis. A 2021 pilot RCT (n=72 OA patients, 8 weeks) found 500 mg/day quercetin significantly reduced serum IL-6, hsCRP, and WOMAC pain scores vs. placebo. It is recognized in OA nutraceutical reviews for its chondroprotective potential.

Resveratrol is a polyphenolic stilbene that inhibits NF-κB signaling, suppresses MMP-13 and ADAMTS-5, and activates SIRT1, collectively reducing inflammatory cartilage degradation in OA. Multiple in vitro and animal studies confirm chondroprotective effects. A clinical pilot RCT found intra-articular resveratrol reduced cartilage loss in an animal OA model, and an early human placebo-controlled pilot trial found resveratrol 1000 mg/day for 6 months reduced WOMAC pain scores and cartilage degradation biomarkers.

Rose hip powder (Rosa canina) contains galactolipids and polyphenols that reduce pro-inflammatory cytokines and downregulate MMP-1, an enzyme responsible for cartilage collagen breakdown. Multiple RCTs using 5 g/day standardized rose hip powder (LitoZin/Hyben Vital) demonstrated significant pain and stiffness reduction in osteoarthritis patients. In vitro studies confirm chondroprotective activity in primary human chondrocytes. Evidence favors whole-fruit preparations containing both seed and shell.

SAMe is an endogenous methyl donor essential for proteoglycan and collagen synthesis in cartilage. Multiple RCTs have found SAMe as effective as NSAIDs for OA pain and function improvement. A meta-analysis of 11 RCTs concluded SAMe was comparable to celecoxib and ibuprofen for OA relief with better safety, and SAMe directly stimulates chondrocyte type II collagen and proteoglycan synthesis.

Early animal research established silicon as a requirement for articular cartilage and connective tissue formation, with deficiency producing skeletal deformities and cartilage with poor collagen content. Silicon is a cofactor for prolyl hydroxylase, an enzyme required for collagen synthesis in cartilage. Direct human intervention data specific to cartilage outcomes remain limited.

Stigmasterol protects cartilage by suppressing matrix metalloproteinases (MMPs) and aggrecanases (ADAMTS) that degrade cartilage matrix, while preserving type II collagen and aggrecan expression. Studies use human OA chondrocytes and animal OA models. No human clinical trials exist.

THIAA reduced cartilage degradation in collagen-induced arthritis mice. Related rho-iso-alpha acids inhibit MMP-13 (the primary type II collagen-degrading enzyme) in chondrosarcoma cells and reduce RANKL-mediated osteoclast activity. THIAA is highlighted in Taylor & Francis literature specifically for its inhibition of NF-κB, TNF-α, and MMP-9 relevant to OA cartilage protection.

Turmeric (Curcuma longa) rhizome contains curcuminoids (primarily curcumin, 2–5%) that inhibit NF-κB, COX-2, 5-LOX, and pro-inflammatory cytokines driving cartilage degradation in OA. A landmark comparative RCT (Kuptniratsaikul et al. 2014, n=367 knee OA patients) found turmeric extract equivalent to ibuprofen 1200 mg/day for knee pain relief. ESCEO guidelines include curcuminoids from turmeric as a recognized OA nutraceutical.

Preclinical and in vitro studies—including work with human chondrocytes from OA patients—show UA improves mitophagy and mitochondrial respiration in cartilage cells and reduces cartilage degeneration. UA promotes anabolic matrix factors and suppresses catabolic enzymes in chondrocytes. Human clinical data on cartilage-specific outcomes are not yet available.

Vitamin C is an essential cofactor for prolyl hydroxylase and lysyl hydroxylase, enzymes required for type II collagen biosynthesis and cross-linking in articular cartilage. Epidemiological data (Framingham OA Study, McAlindon et al. 1996) show higher vitamin C intake was associated with a threefold lower risk of knee OA progression and cartilage loss. Vitamin C also protects chondrocytes from oxidative damage and stimulates proteoglycan synthesis in vitro.

Vitamin D (1,25-dihydroxyvitamin D3) regulates cartilage matrix synthesis via vitamin D receptors on chondrocytes, protecting against cartilage degradation. Low vitamin D status is consistently associated with greater OA severity and faster cartilage loss in epidemiological studies. A 2022 network meta-analysis included vitamin D among top supplements for knee OA pain outcomes, and European OA guidelines recommend correcting vitamin D deficiency in OA patients.

Xylose is the obligatory initiating sugar in the biosynthesis of all chondroitin sulfate and heparan sulfate glycosaminoglycan (GAG) chains on cartilage proteoglycans such as aggrecan. Xylosyltransferase I (XylT-I) catalyzes the transfer of xylose from UDP-xylose to core protein serine residues; its downregulation in late-stage osteoarthritis correlates with depletion of sulfated GAGs and disease progression. This places xylose as a structurally essential biochemical component of cartilage matrix integrity.

Zinc is an essential trace mineral required for chondrocyte proliferation and survival, collagen metalloenzyme activity, and tissue inhibitors of metalloproteinases (TIMPs) preventing excessive cartilage degradation. Synovial fluid zinc concentrations are significantly reduced in OA patients. Low serum zinc correlates inversely with OA severity and elevated cartilage degradation biomarkers in clinical studies. Zinc is a standard component of validated combination joint supplement formulas.

Bamboo silica is traditionally linked to connective tissue support, including cartilage, via its role in collagen and glycosaminoglycan synthesis. Ayurvedic and Unani medicine use tabasheer (bamboo node resin) for joint and connective tissue conditions. Preclinical evidence supports silicon's involvement in collagen and proteoglycan matrix formation.

Bovine cartilage (from cow trachea) provides chondroitin sulfate, type II collagen, and mucopolysaccharides for OA support. An early uncontrolled 5-year study reported significant pain reduction and less radiographic joint degeneration vs. controls. However, WebMD and NCI conclude there is no good scientific evidence from well-designed RCTs specifically for whole bovine cartilage supplements, with the active GAG and collagen constituents better evidenced in purified form.

Cissus sicyoides (Possum Grape) is used in Brazilian and Caribbean traditional medicine for rheumatism, joint pain, and inflammatory conditions. It shares similar phytochemical constituents with Cissus quadrangularis (flavonoids, resveratrol analogs) and traditional indication for joint and bone health. Scientific evidence specifically for cartilage health from clinical trials is limited, placing it primarily in the traditional category.

Dipsacus asper (Xu Duan, 'Continuing Broken') root has been used in TCM since the Shennong Bencao Jing for fracture healing, joint pain, and connective tissue repair. Asperosaponin VI and caffeic acid esters stimulate chondrocyte proliferation and type II collagen synthesis in vitro. Animal OA models confirm reduced cartilage erosion with Dipsacus extract. Chinese Pharmacopoeia approves Xu Duan for bone and joint weakness, but human clinical RCTs for cartilage endpoints are lacking.

Drynaria roosii (Gu Sui Bu, Basket Fern) is a traditional Chinese and Ayurvedic herb used for centuries for fracture healing and joint pain. Its primary bioactive naringin stimulates chondrocyte and osteoblast proliferation and promotes type II collagen expression. In vitro studies confirm anti-OA mechanisms including MMP inhibition in chondrocytes. Animal studies show accelerated fracture and cartilage repair. Human clinical RCTs for cartilage endpoints are not available.

Eucommia (Du Zhong) bark is a foundational TCM herb for strengthening bones, tendons, and joints with over 2000 years of documented use for 'sinew and bone weakness.' Active constituents (chlorogenic acid, aucubin, genipin) promote chondrocyte anabolism and inhibit cartilage-degrading MMP enzymes in preclinical studies. Animal OA models confirm chondroprotective effects. Clinical RCTs for cartilage endpoints are lacking.

Eucommia ulmoides (Du Zhong) bark has been used in Traditional Chinese Medicine for over 2000 years to strengthen bones, tendons, and cartilage. It contains chlorogenic acid, aucubin, and genipin that promote chondrocyte proliferation and inhibit IL-1β–induced MMP expression in vitro. Animal OA models confirm reduced cartilage erosion with Eucommia extract. Human clinical RCT evidence for cartilage endpoints specifically is limited, placing this in the traditional category.

Horsetail is traditionally used to support cartilage and connective tissue, a use codified in the European Pharmacopoeia. The silica in horsetail is proposed to stimulate chondroblasts and support the extracellular matrix proteins essential to cartilage integrity. No dedicated human clinical trials on cartilage outcomes have been conducted, placing this firmly in traditional/preclinical territory.

Mucopolysaccharides (historical term for glycosaminoglycans including chondroitin sulfate) are structural components of articular cartilage and were used as injectable preparations (glycosaminoglycan polysulfate/GAGPS) for OA in Europe from the 1960s until 1992. A 1992 meta-analysis of GAGPS injection trials found significant improvements in OA pain and function. Oral bovine and shark cartilage supplements provide whole-matrix mucopolysaccharides, though modern standard is to use purified characterized GAG preparations.

Shark cartilage is a traditional Chinese medicine ingredient used for bone, joint, and skin health, and contains chondroitin sulfate, mucopolysaccharides, anti-angiogenic proteins, and calcium. While marketed for OA based on chondroitin content, no well-designed RCTs have confirmed clinical benefit for joint cartilage health from whole shark cartilage specifically. The NCI notes that rigorous studies have not validated joint claims, contrasting with strong evidence for isolated chondroitin sulfate.

Herbalists across Western and Asian traditions use Solomon's seal to support cartilage repair and regeneration, particularly in joint wear and repetitive stress injuries. The proposed mechanisms involve anti-inflammatory saponins and mucilaginous constituents that may support synovial fluid and cartilage matrix. No human clinical trial specifically addresses cartilage outcomes.