OBJECTIVE: To clarify the effect of iodoacetic acid(IAA) on the blood system and electrolyte balance, hence further study the intrinsic relation of blood routine parameters and electrolyte levels, major hematological toxicity effects and their pattern after IAA treatment.
METHODS: Forty-eight 21-day-old male SPF grade Sprague-Dawley(SD) rats were gavaged with 0, 6.25, 12.5 and 25 mg/kg IAA for 31 days. After detections of blood routine and plasma inorganic ion levels, Spearman correlation coefficients were performed to evaluate their relationship. Changes in ferritin, transferrin, hepcidin, C-reactive protein and glyceraldehyde-3-phosphate dehydrogenase(GAPDH) were assessed by enzyme-linked immunosorbent assays. The EDock bioinformatics tool was applied to docking model of IAA and GAPDH.
RESULTS: Compared to the control, high-dose IAA exposure had obvious inhibition effect on rat leukocytes with the total number declined by 51.12%, and neutrophils were particularly sensitive to IAA with the number reduced by 73.66%(P<0.01), and rat erythrocytes exhibited a small cell low pigment effect with hemoglobin and hematocrit decreased by 8.60% and 8.70%, respectively(P<0.05). But IAA had little effects on the platelet. Plasma iron, phosphorus, zinc and potassium levels were repressed significantly, while chlorine, sodium and magnesium levels were elevated obviously through IAA exposure. However, plasma calcium levels were hardly affected by IAA. In comparison with the control, iron levels declined by 67.09%, whereas magnesium levels increased by 131.82% in the high-dose group(P<0.01). Overall, correlation analyses uncovered that plasma iron metabolism was most strongly and positively correlated with levels of leukocyte, erythrocyte and platelet system parameters after IAA exposure, and the correlation coefficients of leukocyte number, mean hemoglobin content and mean erythrocyte volume were 0.637, 0.410 and 0.365, respectively(P<0.05). Compared to the control, in the high-dose IAA group, the plasma content of C-reactive protein was significantly upregulated by 13.30%(P<0.05), and plasma levels of transferrin and ferromodulin were also respectively elevated by 12.73% and 11.02%(P<0.05). But plasma levels of ferritin and GAPDH did not differ between groups. The docking model exhibited that IAA could bind to the 150 Cys active site of rat GAPDH did.
CONCLUSIONS: IAA not only had toxic effects on rat leukocytes and the plasma electrolyte balance, but also generated inflammation and iron deficiency, leading to smaller erythrocytes and lower pigment.

Iodoacetic acid (IAA) is an emerging unregulated iodinated disinfection byproduct with high toxicity and widespread exposure. IAA has potential reproductive toxicity and could damage male reproduction. However, the underlying mechanisms and toxicological targets of IAA on male reproductive impairment are still unclear, and thus Sprague-Dawley rats and Leydig cells were used in this work to decode these pending concerns. Results showed that after IAA exposure, the histomorphology and ultrastructure of rat testes were abnormally changed, numbers of Leydig cells were reduced, the hypothalamic-pituitary-testis (HPT) axis was disordered, and testosterone biosynthesis was inhibited. Proteomics analyses displayed that oxidative stress, endoplasmic reticulum stress, and steroid hormone biosynthesis were involved in IAA-caused reproductive injury. Antioxidant enzymes were depleted, while levels of ROS, MDA, 8-OHdG, and γ-H2A.X were increased by IAA. IAA triggered oxidative stress and DNA damage, and then activated the GRP78/IRE1/XBP1s and cGAS/STING/NF-κB pathways in Leydig cells. The two signaling pathways constructed an interactive network by synergistically regulating the downstream transcription factor CHOP, which in turn directly bound to and negatively modulated steroidogenic StAR, finally refraining testosterone biosynthesis in Leydig cells. Collectively, IAA as a reproductive toxicant has anti-androgenic effects, and the GRP78/IRE1 and cGAS/STING pathway crosstalk through CHOP facilitates IAA-mediated testosterone decline.

Osteoarthritis (OA) is a chronic degenerative joint disease that causes chronic pain, swelling, stiffness, disability, and significantly reduces the quality of life. Typically, OA is treated using painkillers and non-steroidal anti-inflammatory drugs (NSAIDs). While current pharmacologic treatments are common, their potential side effects have prompted exploration into functional dietary supplements. Recently, eggshell membrane (ESM) has emerged as a potential functional ingredient for joint and connective tissue disorders due to its clinical efficacy in relieving joint pain and stiffness. Despite promising clinical evidence, the effects of ESM on OA progression and its mechanism of action remain poorly understood. This study evaluated the efficacy of Ovomet®, a powdered natural ESM, against joint pain and disease progression in a monosodium iodoacetate (MIA)-induced rodent model of OA in mice and rats. The results demonstrate that ESM significantly alleviates joint pain and attenuates articular cartilage destruction in both mice and rats that received oral supplementation for 5 days prior to OA induction and for 28 days thereafter. Interestingly, ESM significantly inhibited mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), as well as inflammatory mediators, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase in the knee joint cartilage at the early stage of OA, within 7 days after OA induction. However, this effect was not observed in the late stage at 28 days after OA induction. ESM further attenuates the induction of protein expression for cartilage-degrading enzymes like matrix metalloproteinase (MMPs) 3 and 13, and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5), in the late-stage. In addition, MIA-induced reduction of the protein expression levels of cartilage components, cartilage oligomeric matrix protein (COMP), aggrecan (ACAN) and collagen type II α-1 chain (COL2α1), and cartilage extracellular matrix (ECM) synthesis promoting transcriptional factor SRY-Box 9 (SOX-9) were increased via ESM treatment in the cartilage tissue. Our findings suggest that Ovomet®, a natural ESM powder, is a promising dietary functional ingredient that can alleviate pain, inflammatory response, and cartilage degradation associated with the progression of OA.

BACKGROUND: This study aimed to validate alterations in the gene expression of DNA methylation-related enzymes and global methylation in the peripheral blood mononuclear cell (PBMC) and synovial tissues of animal hip osteoarthritis (OA) models.
METHODS: Animals were assigned to the control (no treatment), sham (25 µL of sterile saline), and OA (25 µL of sterile saline and 2 mg of monoiodoacetate) groups. Microcomputed tomography scan, histopathological assessment and pain threshold measurement were performed after induction. The mRNA expression of the DNA methylation machinery genes and global DNA methylation in the PBMC and hip synovial tissue were evaluated.
RESULTS: The OA group presented with hip joint OA histopathologically and radiologically and decreased pain threshold. The mRNA expression of DNA methyltransferase (Dnmt 3a), ten-eleven translocation (Tet) 1 and Tet 3 in the synovial tissue of the OA group was significantly upregulated. Global DNA methylation in the synovial tissue of the OA group was significantly higher than that of the control and sham groups.
CONCLUSIONS: The intra-articular administration of monoiodoacetate induced hip joint OA and decreased pain threshold. The DNA methylation machinery in the synovial tissues of hip OA was altered.

BACKGROUND: The increasing incidence of osteoarthritis (OA), especially among the elderly population, highlights the need for more efficacious treatments that go beyond mere symptomatic relief. Tinospora crispa (L.) Hook. f. & Thomson (TC) boasts a rich traditional heritage, widespread use in Ayurveda, traditional Chinese medicine (TCM), and diverse indigenous healing practices throughout Southeast Asia for treating arthritis, rheumatism, fever, and inflammation.
OBJECTIVE: This study investigates the anti-inflammatory and chondroprotective potential of TC stem extracts, including ethanolic TC extract (ETCE) and aqueous TC extract (ATCE), in modulating OA pathogenesis through in vitro and in vivo approaches.
METHODS: The study utilized LC-MS/MS to identify key compounds in TC stem extracts. In vitro experiments assessed the antioxidative and anti-inflammatory properties of ETCE and ATCE in activated macrophages, while an in vivo monoiodoacetate (MIA)-induced OA rat model evaluated the efficacy of ETCE treatment. Key markers of oxidative stress, such as superoxide dismutase (SOD) and catalase (CAT), were assessed alongside pro-inflammatory cytokines TNF-α and IL-1β, and matrix-degrading enzymes, matrix metalloproteinase (MMP 13 and MMP 3), to evaluate the therapeutic effects of TC stem extracts on OA.
RESULTS: Chemical profiling of the extracts was conducted using LC-MS/MS in positive ionization, identifying seven compounds, including pseudolaric acid B, stylopine, and reticuline, which were reported for the first time in this species. The study utilized varying concentrations of TC stem extracts, specifically 6.25-25 μg/mL for in vitro assays and 500 mg/kg for in vivo studies. Our findings also revealed that both ETCE and ATCE exhibit dose-dependent reduction in reactive oxygen species (41%-52%) and nitric oxide (NO) levels (50% and 72%), with ETCE displaying superior antioxidative efficacy and marked anti-inflammatory properties, significantly reducing TNF-α and IL-6 at concentrations above 12.5 μg/mL. In the MIA-induced OA rat model, ETCE treatment notably outperformed ATCE, markedly lowering TNF-α (1.91 ± 0.37 pg/mL) and IL-1β (26.30 ± 3.68 pg/mL) levels and effectively inhibiting MMP 13 and MMP 3 enzymes. Furthermore, macroscopic and histopathological assessments, including ICRS scoring and OARSI grading, indicate that TC stem extracts reduce articular damage and proteoglycan loss in rat knee cartilage. These results suggest that TC stem extracts may play a role in preventing cartilage degradation and potentially alleviating inflammation and pain associated with OA, though further studies are needed to confirm these effects.
CONCLUSIONS: This study highlights the potential of TC stem extracts as a novel, chondroprotective therapeutic avenue for OA management. By targeting oxidative stress, pro-inflammatory cytokines, and cartilage-degrading enzymes, TC stem extracts promise to prevent cartilage degradation and alleviate inflammation and pain associated with OA.

Osteoarthritis (OA) is a debilitating joint disorder characterized by cartilage degradation and chronic inflammation, accompanied by high oxidative stress. In this study, we utilized the monosodium iodoacetate (MIA)-induced OA model to investigate the efficacy of oligo-fucoidan-based formula (FF) intervention in mitigating OA progression. Through its capacity to alleviate joint bearing function and inflammation, improvements in cartilage integrity following oligo-fucoidan-based formula intervention were observed, highlighting its protective effects against cartilage degeneration and structural damage. Furthermore, the oligo-fucoidan-based formula modulated the p38 signaling pathway, along with downregulating cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, contributing to its beneficial effects. Our study provides valuable insights into targeted interventions for OA management and calls for further clinical investigations to validate these preclinical findings and to explore the translational potential of an oligo-fucoidan-based formula in human OA patients.

BACKGROUND: The development of neuropathic pain (NP) is one of the reasons why the pain is difficult to treat, and microglial activation plays an important role in NP. Recently, platelet-rich plasma (PRP) has emerged as a novel therapeutic method for knee osteoarthritis (KOA). However, it\'s unclarified whether PRP has analgesic effects on NP induced by KOA and the underlying mechanisms unknown.
OBJECTIVE: To observe the analgesic effects of PRP on NP induced by KOA and explore the potential mechanisms of PRP in alleviating NP.
METHODS: KOA was induced in male rats with intra-articular injections of monosodium iodoacetate (MIA) on day 0. The rats received PRP or NS (normal saline) treatment at days 15, 17, and 19 after modeling. The Von Frey and Hargreaves tests were applied to assess the pain-related behaviors at different time points. After euthanizing the rats with deep anesthesia at days 28 and 42, the corresponding tissues were taken for subsequent experiments. The expression of activating transcription factor 3 (ATF3) in dorsal root ganglia (DRG) and ionized-calcium-binding adapter molecule-1(Iba-1) in the spinal dorsal horn (SDH) was detected by immunohistochemical staining. In addition, the knee histological assessment was performed by hematoxylin-eosin (HE) staining.
RESULTS: The results indicated that injection of MIA induced mechanical allodynia and thermal hyperalgesia, which could be reversed by PRP treatment. PRP downregulated the expression of ATF3 within the DRG and Iba-1 within the SDH. Furthermore, an inhibitory effect on cartilage degeneration was observed in the MIA + PRP group only on day 28.
CONCLUSIONS: These results indicate that PRP intra-articular injection therapy may be a potential therapeutic agent for relieving NP induced by KOA. This effect could be attributed to downregulation of microglial activation and reduction in nerve injury.

Iodoacetic acid (IAA) is a halogenated disinfection by-product of growing concern due to its high cytotoxicity, genotoxicity, endocrine disruptor effects, and potential carcinogenicity. However, the data on distribution and excretion of IAA after ingestion by mammals are still scarce. Here, we developed a reliable and validated method for detecting IAA in biological specimens (plasma, urine, feces, liver, kidney, and tissues) based on modified QuEChERS sample preparation combined with gas chromatography-tandem triple quadrupole mass spectrometry (GC-MS/MS). The detection method for IAA exhibited satisfactory recovery rates (62.6-108.0%) with low relative standard deviations (RSD < 12.3%) and a low detection limit for all biological matrices ranging from 0.007 to 0.032 ng/g. The study showed that the proposed method was reliable and reproducible for analyzing IAA in biological specimens. It was successfully used to detect IAA levels in biological samples from rats given gavage administration. The results indicated that IAA was found in various tissues and organs, including plasma, thyroid, the liver, the kidney, the spleen, gastrointestinal tract, and others, 6 h after exposure. This study provides the first data on the in vivo distribution in and excretion of IAA by mammals following oral exposure.

Osteoarthritis is a widespread chronic degenerative disease marked by the deterioration of articular cartilage, modifications in subchondral bone, and a spectrum of symptoms, including pain, stiffness, and disability. Ultimately, this condition impairs the patient\'s quality of life. This study aimed to evaluate the therapeutic efficacy of standardized Boswellia serrata gum resin extract (BSRE) in a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis. A total of 60 rats were allocated into six groups: normal control group (NC), osteoarthritis control (injected with MIA, OC), O + B50 (injected with MIA and treated with 50 mg/kg body weight (BW) BSRE), O + B75 (injected with MIA and treated with 75 mg/kg BW BSRE), O + B100 (injected with MIA and treated with 100 mg/kg BW BSRE), and O + M (injected with MIA and treated with 150 mg/kg BW methyl sulfonyl methane). Several parameters, including knee joint swelling, histopathological changes, and the expression of collagen type II alpha 1 (COL2A1) and aggrecan, were comprehensively assessed. Concurrently, the serum levels and mRNA expression of inflammatory mediators, cytokines, and matrix metalloproteinases (MMPs) were analyzed in both the serum and knee joint synovium. The results demonstrated that BSRE significantly mitigated knee joint swelling, cartilage destruction, and tissue deformation. Notably, BSRE administration markedly upregulated the expression of COL2A1 and aggrecan while concurrently reducing levels of nitric oxide, prostaglandin E2, leukotriene B4, interleukin (IL)-6, and tumor necrosis factor (TNF)-α. Furthermore, a substantial decrease was observed in the mRNA expression of inducible nitric oxide synthase, cyclooxygenase-2, 5-lipoxygenase, IL-6, TNF-α and MMP-3 and -13, thereby indicating promising therapeutic implications for osteoarthritis. In conclusion, BSRE exhibited anti-inflammatory properties and inhibited cartilage matrix degradation in a rat model of MIA-induced osteoarthritis, with the O + B100 group showing significant reductions in swelling and notable improvements in joint cartilage damage. These findings illuminate the preventive and therapeutic potential of BSRE for osteoarthritis treatment, emphasizing the criticality of exhaustive evaluation of novel compounds.

OBJECTIVE: Vertebral endplate lesions (EPLs) caused by severe disk degeneration are associated with low back pain. However, its pathophysiology remains unclear. In this study, we aimed to develop a vertebral EPL rat model mimicking severe intervertebral disk (IVD) degeneration by injecting monosodium iodoacetate (MIA) into the IVDs and evaluating it by assessing pain-related behavior, micro-computed tomography (CT) findings, and histological changes.
METHODS: MIA was injected into the L4-5 and L5-6 IVDs of Sprague-Dawley rats. Their behavior was examined by measuring the total distance traveled and the total number of rearing in an open square arena. Bone alterations and volume around the vertebral endplate were assessed using micro-CT. Safranin-O staining, immunohistochemistry, and tartrate-resistant acid phosphatase (TRAP) staining were performed for histological assessment.
RESULTS: The total distance and number of rearing times in the open field were significantly reduced in a time-dependent manner. Micro-CT revealed intervertebral osteophytes and irregularities in the endplates at 12 weeks. The bone volume/tissue volume (BV/TV) around the endplates significantly increased from 6 weeks onward. Safranin-O staining revealed severe degeneration of IVDs and endplate disorders in a dose- and time-dependent manner. Calcitonin gene-related peptide-positive nerve fibers significantly increased from 6 weeks onward. However, the number of osteoclasts decreased over time.
CONCLUSIONS: Our rat EPL model showed progressive morphological vertebral endplate changes in a time- and concentration-dependent manner, similar to the degenerative changes in human IVDs. This model can be used as an animal model of severe IVD degeneration to better understand the pathophysiology of EPL.