Taurine Supplementation Inhibits the Expression of Atrogin-1 and MURF-1, Protein Degradation Marker Genes, in Skeletal Muscle of C26-Induced Cachexia Mouse Model.

This study was designed to investigate the therapeutic effects of taurine in attenuating muscle atrophy. C26 carcinoma cells were cultured and injected into the scapulae of Balb/c mice with 1 × 106 cells. Taurine (200 µl suspension) was orally administered at the concentration of 200 mg/kg of body weight for 2 weeks. Femur muscle tissue, spleen, and gonadal fat tissue were collected and weighed. Muscle tissue was stained by H&E for histopathological analysis. The transcriptional expression of atrogin-1 and MuRF-1 gene was checked by real-time PCR. C26 cells, which induced tumor growth, caused a loss in muscle mass and gonadal fat tissue mass. Simultaneously, there was an increase in spleen and tumor tissue mass. In contrast, taurine supplementation showed a downregulatory effect on the transcriptional expression profile of muscle degradative factors atrogin-1 and MuRF-1. Our findings suggest that taurine has the potential to inhibit muscle atrophy and can be developed as a safe treatment option against muscle loss in sarcopenia patients.

Multifaceted Physiological Roles of Adiponectin in Inflammation and Diseases.

Adiponectin is the richest adipokine in human plasma, and it is mainly secreted from white adipose tissue. Adiponectin circulates in blood as high-molecular, middle-molecular, and low-molecular weight isoforms. Numerous studies have demonstrated its insulin-sensitizing, anti-atherogenic, and anti-inflammatory effects. Additionally, decreased serum levels of adiponectin is associated with chronic inflammation of metabolic disorders including Type 2 diabetes, obesity, and atherosclerosis. However, recent studies showed that adiponectin could have pro-inflammatory roles in patients with autoimmune diseases. In particular, its high serum level was positively associated with inflammation severity and pathological progression in rheumatoid arthritis, chronic kidney disease, and inflammatory bowel disease. Thus, adiponectin seems to have both pro-inflammatory and anti-inflammatory effects. This indirectly indicates that adiponectin has different physiological roles according to an isoform and effector tissue. Knowledge on the specific functions of isoforms would help develop potential anti-inflammatory therapeutics to target specific adiponectin isoforms against metabolic disorders and autoimmune diseases. This review summarizes the current roles of adiponectin in metabolic disorders and autoimmune diseases.

Interleukin 17 under hypoxia mimetic condition augments osteoclast mediated bone erosion and expression of HIF-1α and MMP-9.

Interleukin 17 (IL-17) and hypoxia have been implicated to play a key role in rheumatoid arthritis (RA). In this study, the combined treatment of IL-17 and cobalt chloride (CoCl2), a hypoxia mimetic significantly increased the osteoclast formation and the expression of TRAP and MMP-9 in RAW 264.7 macrophage cells in the presence of RANKL and M-CSF. The unified effect of IL-17 and CoCl2 markedly increased osteoclast mediated bone erosion through the activation of RANKL/NF-κB/NFATc1 signaling pathway. The treatment of IL-17 in combination with CoCl2 further potentiated the protein and mRNA expression of HIF-1α and MMP-9 in rat synovial macrophages. Conversely, the blockage of HIF-1α expression with BAY87-2243 abrogated the IL-17 and CoCl2 mediated expression of HIF-1α and MMP-9. Further, the knockdown of IL-17RA using siRNA reversed the IL-17 and CoCl2 induced expression of HIF-1α in synovial macrophages. In conclusion, IL-17 synergizes with CoCl2 induced hypoxic condition to augment osteoclast mediated bone erosion and synovial macrophages mediated RA pathogenesis.

Majoon ushba, a polyherbal compound ameliorates rheumatoid arthritis via regulating inflammatory and bone remodeling markers in rats.

The present study was aimed to investigate the anti-arthritic effect of majoon ushba (MU) and its underlying mechanism in adjuvant induced arthritis (AIA) rats. Arthritis was induced by intradermal injection of complete freund's adjuvant (0.1ml) into the right hind paw of the Wistar albino rats. MU (1000mg/kg/b.wt) and methotrexate (3mg/kg/b.wt) were administered from day 11 to day 18th for 8days after adjuvant induction. We have found that MU treatment significantly increased the level of anti-inflammatory cytokine (IL-10) and inhibited the over production of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) and monocyte chemoattractant protein-1 (MCP-1) (ELISA) in the serum of adjuvant-induced arthritic rats. The mRNA expression of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, and IL-17), inflammatory enzymes (inducible nitric oxide synthase (iNOS) and cyclo-oxygenase-2 (COX-2)), MCP-1, receptor activator of nuclear factor-kB ligand (RANKL) and transcription factors (NF-кB and AP-1) (Real-Time PCR) was found significantly downregulated in the synovial tissues of MU treated arthritic rats. In addition, the protein expression of NF-кB, IL-17, COX-2, and RANKL (western blotting and immunohistochemistry analysis) was found reduced. On the other hand, osteoprotegerin (OPG), a bone remodeling marker was found to be elevated in synovial tissues of MU treated arthritic rats. Furthermore, MU treatment prevented body weight loss and reduced the joint paw edema, cell infiltration, cartilage and bone degradation as evidenced by the histopathological and radiological analysis. In conclusion, our current findings provide scientific evidence for the traditional claim of MU as an anti-arthritic drug.

Majoon Chobchini attenuates arthritis disease severity and RANKL-mediated osteoclastogenesis in rheumatoid arthritis.

Majoon Chobchini, a polyherbal Unani compound, has been used holistically in India to treat rheumatoid arthritis. However, the potential mechanism underlying the antiarthritic efficacy of Majoon Chobchini has not been elucidated so far. This study was aimed to explore the underlying molecular mechanism and scientifically validate the therapeutic basis of Majoon Chobchini in rheumatoid arthritis (RA). The anti-arthritic efficacy of Majoon Chobchini was demonstrated in vivo using complete Freund's adjuvant-induced arthritic rat model and adjuvant-induced arthritic fibroblast-like synoviocytes (AA-FLS). The expression of pro-inflammatory mediators and enzymes was evaluated in the serum and synovial tissues of adjuvant-induced arthritis (AIA) rats. In-vitro, AA-FLS, and bone marrow macrophages (BMMs) were co-cultured to evaluate the formation and activity of osteoclasts using TRAP staining analysis and pit formation assay, respectively. RANKL and OPG levels were detected using western blotting and qRT-PCR analysis. Furthermore, the involvement of JAK-STAT-3 signaling in the therapeutic efficacy of Majoon Chobchini was evaluated both in vivo and in vitro. Majoon Chobchini significantly reversed the physical symptoms in AIA rats with reduced expression of pro-inflammatory cytokines and enzymes. Notably, Majoon Chobchini alleviated cartilage degradation and bone erosion in AIA rats via inhibiting the activation of the JAK-STAT-3 signaling pathway in the AIA rats. Consistent with its effect in vivo, Majoon Chobchini decreased osteoclast inducing potential of AA-FLS and thus attenuated osteoclast formation and bone resorption in vitro. Taken together, our findings suggest that the JAK/STAT-3 signaling inhibition may underlie the mechanism through which Majoon Chobchini provides relief against RA symptoms. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02985-4.

Taurine Stimulates Thermoregulatory Genes in Brown Fat Tissue and Muscle without an Influence on Inguinal White Fat Tissue in a High-Fat Diet-Induced Obese Mouse Model.

This study was conducted to investigate if taurine supplementation stimulates the induction of thermogenic genes in fat tissues and muscles and decipher the mechanism by which taurine exerts its anti-obesity effect in a mildly obese ICR (CD-1®) mouse model. Three groups of ICR mice were fed a normal chow diet, a high-fat diet (HFD), or HFD supplemented with 2% taurine in drinking water for 28 weeks. The expression profiles of various genes were analyzed by real time PCR in interscapular brown adipose tissue (BAT), inguinal white adipose tissue (iWAT), and the quadriceps muscles of the experimental groups. Genes that are known to regulate thermogenesis like PGC-1α, UCP-1, Cox7a1, Cox8b, CIDE-A, and ß1-, ß2-, and ß3-adrenergic receptors (ß-ARs) were found to be differentially expressed in the three tissues. These genes were expressed at a very low level in iWAT as compared to BAT and muscle. Whereas, HFD increased the expression of these genes. Taurine supplementation stimulated the expression of UCP-1, Cox7a1, and Cox8b in BAT and only Cox7a1 in muscle, while there was a decrease in iWAT. In contrast, fat deposition-related genes, monoamine oxidases (MAO)-A, and -B, and lipin-1, were decreased by taurine supplementation only in iWAT and not in BAT or muscle. In conclusion, the potential anti-obesity effects of taurine may be partly due to upregulated thermogenesis in BAT, energy metabolism of muscle, and downregulated fat deposition in iWAT.

Ferulic acid, a dietary polyphenol suppresses osteoclast differentiation and bone erosion via the inhibition of RANKL dependent NF-κB signalling pathway.

AIMS: Bone erosion induced by enhanced osteoclast formation is a debilitating pathological phenomenon in rheumatoid arthritis (RA). Recent finding has revealed that ferulic acid is associated with reduced osteoclast differentiation and bone erosion. However, the underlying mechanism through which ferulic acid inhibited osteoclast differentiation and bone erosion still remains to be elucidated. This study assessed the therapeutic effects of ferulic acid on osteoclast differentiation and bone erosion by targeting RANKL dependent NF-κB pathway. MAIN METHODS: RAW 264.7 monocyte/macrophage cells were left untreated/treated with 25, 50 and 100 µM ferulic acid prior to stimulation with/without RANKL and M-CSF. Osteoclast differentiation and formation was assessed by SEM and TRAP analysis whereas its functional activity of bone erosion was determined by pit formation assay. Crucial transcription factors (NF-κBp-65, NFATc1 and c-Fos) and osteoclast specific genes (TRAP, MMP-9 and Cathepsin K) were evaluated by quantitative RT-PCR. Further, the protein level expression of NF-κBp-65, NFAtc1, c-Fos and MMP-9 was assessed using western blot analysis. KEY FINDINGS: Our results demonstrated that ferulic acid significantly attenuated RANKL induced osteoclast differentiation as evidenced from SEM and TRAP staining analysis. A remarkable decrease in the bone resorption activity of osteoclasts was also noticed upon ferulic acid treatment. In addition, the down-regulation of RANKL induced NF-κB activation and its associated downstream factors like NFATc1, c-Fos, TRAP, Cathepsin K and MMP-9 was also observed upon ferulic acid treatment. SIGNIFICANCE: Thus, our findings evidence the anti-stimulatory and anti-resorptive role of ferulic acid via the inhibition of RANKL dependent NF-κB signalling pathway.

Trikatu, an herbal compound ameliorates rheumatoid arthritis by the suppression of inflammatory immune responses in rats with adjuvant-induced arthritis and on cultured fibroblast like synoviocytes via the inhibition of the NFκB signaling pathway.

The present study was designed to investigate the potential therapeutic effect of trikatu, an herbal compound and its underlying molecular mechanism in rats with adjuvant-induced arthritis (AIA). Our results indicate that trikatu (1000 mg/kg/b.wt. oral) administration suppressed the production of pro-inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, and monocyte chemoattractant protein (MCP)-1) and downregulated the mRNA expression levels of inflammatory mediators (TNF-α, IL-1ß, IL-6, IL-17, MCP-1, receptor activator of nuclear factor kappa B ligand (RANKL), cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS)) and transcription factors (nuclear factor kappa B 65 (NFкB-p65) and activator protein-1 (AP-1)) in cultured AIA-fibroblast like synoviocytes and synovial tissue of AIA rats. Consistently, the protein expression of NFкB-p65, IL-17, TNF-α, COX-2, and RANKL was also dramatically reduced in cultured AIA-fibroblast like synoviocytes and synovial tissue of AIA rats by trikatu treatment. In addition, trikatu suppressed the expression and phosphorylation of NFкB-p65 similar to the Bay 11-7082 (NFкB inhibitor) in cultured AIA-fibroblast like synoviocytes. Furthermore, trikatu alleviated the histopathology of joint of arthritic rats. Overall, these data highlights that trikatu could be a promising alternative modality for the possible treatment of rheumatoid arthritis and other inflammatory diseases.

Majoon ushba, a polyherbal compound, suppresses pro-inflammatory mediators and RANKL expression via modulating NFкB and MAPKs signaling pathways in fibroblast-like synoviocytes from adjuvant-induced arthritic rats.

Fibroblast-like synoviocytes (FLS) are inhabitant mesenchymal cells of synovial joints and have been recognized to play an imperative role in the immunopathogenesis of rheumatoid arthritis (RA). Blocking these pathological roles of FLS provides a potentially important therapeutic strategy for the treatment for RA. A recent study had confirmed that majoon ushba (MU), a polyherbal unani compound, possesses anti-arthritic effects in in vivo. Toward this direction, an effort has been made to understand the effect of MU on FLS derived from adjuvant-induced arthritis (AIA) rats. Here, we observed that MU administration (100-300 µg/ml) significantly inhibited the expression and phosphorylation of NFкB-p65 protein similar to that of the Bay 11-7082 (NFкB inhibitor) in NFкB signaling pathway and suppressed the protein expression of ERK1/2 and JNK1/2 in MAPKs signaling pathway in AIA-FLS. In addition, the protein expression of TNF-α, IL-17, RANKL, and iNOS was also found reduced. MU treatment significantly inhibited the mRNA expression of pro-inflammatory mediators (TNF-α, IL-1ß, IL-6, MCP-1, IL-17, iNOS, and COX-2), transcription factors (NFкB-p65 and AP-1), and RANKL and attenuated the overproduction of TNF-α, IL-1ß, IL-6, and MCP-1 (ELISA) in AIA-FLS. Furthermore, MU treatment significantly inhibited the level of lipid peroxidation, lysosomal enzymes release, and glycoproteins and increased antioxidant status (superoxide dismutase and catalase) in AIA-FLS. In conclusion, the results of this study provide evidence that MU possesses anti-inflammatory effect against AIA-FLS through the decrease in pro-inflammatory mediators expression by suppressing NFкB and MAPKs signaling pathways.

Targeting inflammatory mediators with ferulic acid, a dietary polyphenol, for the suppression of monosodium urate crystal-induced inflammation in rats.

AIMS: The aim of this study was to investigate the anti-inflammatory effect of ferulic acid, a dietary phenol, on monosodium urate (MSU) crystal-induced inflammation in rats, an experimental model for acute gouty arthritis. For the purpose of comparison, colchicine was used as a reference drug. MAIN METHODS: Paw edema, levels/activities of elastase, lysosomal enzymes (acid phosphatase and ß-galactosidase), nitric oxide, lipid peroxidation, antioxidant status and pro-inflammatory cytokines (tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1ß), and histology of ankle joints were evaluated in rats with MSU crystal-induced inflammation. The messenger RNA (mRNA) expression of pro-inflammatory cytokines (TNF-α and IL-1ß), NLRP3 (nucleotide oligomerization domain (NOD)-like receptor family, pyrin domain containing 3) inflammasomes, caspase-1, and the transcription factor nuclear factor kappa B p65 (NF-κB p65) was determined by real-time polymerase chain reaction (PCR) analysis. The protein expression of NF-κB p65 and TNF-α was detected by immunohistochemical analysis. Further, a molecular docking analysis was conducted to determine the ligand efficiency of ferulic acid towards NF-κB, apoptosis-associated speck-like protein containing a CARD (PYCARD/ASC), NLRP3, and pro-caspase-1. KEY FINDINGS: In the joint homogenate of rats with MSU crystal-induced inflammation, treatment with ferulic acid (30mg/kg body weight (b.wt)) decreased paw edema; the level/activity of elastase, lysosomal enzymes, nitric oxide, lipid peroxidation, and pro-inflammatory cytokines (TNF-α and IL-1ß); and the mRNA expression of NLRP3 inflammasomes, caspase-1, pro-inflammatory cytokines, and NF-κB p65. In addition, the protein expression of NF-κB p65 and TNF-α was also found to be significantly decreased. However, the antioxidant status (superoxide dismutase (SOD) and catalase (CAT)) were found to be increased. The molecular docking analysis showed that ferulic acid exhibited significant ligand efficiency towards pro-caspase-1, NF-κB, PYCARD/ASC, and NLRP3. SIGNIFICANCE: Our findings demonstrate the potential anti-inflammatory effect of ferulic acid on MSU crystal-induced inflammation in rats.