Effects of Exercise Combined with Undenatured Type II Collagen on Endurance Capacity, Antioxidant Status, Muscle Lipogenic Genes and E3 Ubiquitin Ligases in Rats

Beneficial effects of a novel polyherbal formulation on the skeletal muscle antioxidant status, inflammation, and muscle-signaling proteins in exercised rats

Background/aim

Exhausting exercise can damage muscle tissue due to free radical interactions. It is hypothesized that the increase in free radicals following muscle injury, either due to oxidative damage to biomolecules or the activation of inflammatory cytokines, may lead to secondary muscle damage. This study investigated the effects of a novel joint health formula (JHF) containing bisdemethoxycurcumin-enriched curcumin, 3-O-Acetyl-11-keto-beta-boswellic acid-enriched Boswellia (AKBA), and Ashwagandha on exhaustion time, grip strength, antioxidant status, and muscle-signaling proteins in exhaustively exercised rats.

Materials and methods

Twenty-eight rats were divided into four groups: Control (C), exercise (E), E + JHF 100 (100 mg/kg), and E + JHF 200 (200 mg/kg).

Results

An increase in time to exhaustion and grip strength was recorded with JHF supplementation in a dose-dependent manner (p < 0.0001). In addition, serum and muscle lactate dehydrogenase, malondialdehyde, myoglobin, creatine kinase, and lactic acid concentrations were decreased in the groups supplemented with JHF, particularly at the high dose of JHF (200 mg/kg) (p < 0.0001 for all). JHF supplementation also increased antioxidant enzyme activities and suppressed the production of inflammatory cytokines compared to the exercise group (p < 0.0001). Moreover, JHF reduced the levels of PGC-1α, p-70S6K1, MAFbx, MuRF1, and p-mTOR proteins in muscle tissue compared to the exercise group (p < 0.05), being more effective at high doses.

Conclusion

These findings show that JHF might reduce muscle damage by modulating antiinflammatory, antioxidant, and muscle mass regulatory pathways in exhausted training rats. At the same time, JHF improved exercise performance and grip strength.

Aerobic Exercise Ameliorates Muscle Atrophy Induced by Methylglyoxal via Increasing Gastrocnemius and Extensor Digitorum Longus Muscle Sensitivity

Muscle atrophy is characterized by the loss of muscle function. Many efforts are being made to prevent muscle atrophy, and exercise is an important alternative. Methylglyoxal is a well-known causative agent of metabolic diseases and diabetic complications. This study aimed to evaluate whether methylglyoxal induces muscle atrophy and to evaluate the ameliorative effect of moderate-intensity aerobic exercise in a methylglyoxal-induced muscle atrophy animal model. Each mouse was randomly divided into three groups: control, methylglyoxal-treated, and methylglyoxal-treated within aerobic exercise. In the exercise group, each mouse was trained on a treadmill for 2 weeks. On the last day, all groups were evaluated for several atrophic behaviors and skeletal muscles, including the soleus, plantaris, gastrocnemius, and extensor digitorum longus were analyzed. In the exercise group, muscle mass was restored, causing in attenuation of muscle atrophy. The gastrocnemius and extensor digitorum longus muscles showed improved fiber cross-sectional area and reduced myofibrils. Further, they produced regulated atrophy-related proteins (i.e., muscle atrophy F-box, muscle RING-finger protein-1, and myosin heavy chain), indicating that aerobic exercise stimulated their muscle sensitivity to reverse skeletal muscle atrophy. In conclusion, shortness of the gastrocnemius caused by methylglyoxal may induce the dynamic imbalance of skeletal muscle atrophy, thus methylglyoxal may be a key target for treating skeletal muscle atrophy. To this end, aerobic exercise may be a powerful tool for regulating methylglyoxal-induced skeletal muscle atrophy.

In Vivo Evaluation of Collagen and Chitosan Scaffold, Associated or Not with Stem Cells, in Bone Repair

Natural polymers are increasingly being used in tissue engineering due to their ability to mimic the extracellular matrix and to act as a scaffold for cell growth, as well as their possible combination with other osteogenic factors, such as mesenchymal stem cells (MSCs) derived from dental pulp, in an attempt to enhance bone regeneration during the healing of a bone defect. Therefore, the aim of this study was to analyze the repair of mandibular defects filled with a new collagen/chitosan scaffold, seeded or not with MSCs derived from dental pulp. Twenty-eight rats were submitted to surgery for creation of a defect in the right mandibular ramus and divided into the following groups: G1 (control group; mandibular defect with clot); G2 (defect filled with dental pulp mesenchymal stem cells-DPSCs); G3 (defect filled with collagen/chitosan scaffold); and G4 (collagen/chitosan scaffold seeded with DPSCs). The analysis of the scaffold microstructure showed a homogenous material with an adequate percentage of porosity. Macroscopic and radiological examination of the defect area after 6 weeks post-surgery revealed the absence of complete repair, as well as absence of signs of infection, which could indicate rejection of the implants. Histomorphometric analysis of the mandibular defect area showed that bone formation occurred in a centripetal fashion, starting from the borders and progressing towards the center of the defect in all groups. Lower bone formation was observed in G1 when compared to the other groups and G2 exhibited greater osteoregenerative capacity, followed by G4 and G3. In conclusion, the scaffold used showed osteoconductivity, no foreign body reaction, malleability and ease of manipulation, but did not obtain promising results for association with DPSCs.

The effect of oral administration of undenatured type II collagen on monosodium iodoacetate-induced osteoarthritis in young and old rats

We investigated whether different doses of undenatured type II collagen (undenatured collagen, UC-II) help improve monosodium iodoacetate (MIA)-induced (osteoarthritis) OA in young and old rats. A total of 70 rats were divided into five groups: (1) control; (2) MIA (a single intra-articular injection of MIA); (3)-(5) MIA+ Undenatured Collagen with various oral doses (0.66, 1.33, and 2 mg/kg). The results showed that all doses of undenatured collagen in both age groups reduced knee diameter, while the two higher doses (1.33 mg/kg and 2 mg/kg) reduced the Mankin score and increased most gait measurements as early as day 14 compared to the MIA rats. However, the 2 mg/kg dose showed the best efficacy in improving Mankin score and gait measurements by 28 days post-OA induction. In young but not old rats, all doses of undenatured collagen reduced the Kellgren-Lawrence score compared to the MIA group. Undenatured collagen reduced the levels of most inflammatory and cartilage breakdown markers in serum and knee joint cartilage in both age groups. In conclusion, this data suggests that while all doses of undenatured collagen supplementation may ameliorate MIA-induced OA symptoms, the higher doses showed faster improvement in gait measurements and were more efficacious for overall joint health in rats.

Molecular Mechanisms of Action of Undenatured Type II Collagen: Experimental and Clinical Evidence

In the treatment of joint diseases, including osteoarthritis (OA), the use of standardized extracts of undenatured type II collagen (UDC-II) is promising. It is known that UDC-II is involved in the regulation of innate and adaptive immunity (reduction of autoimmune reactions that stimulate cartilage degradation) and in the reduction of chronic inflammation activity (modulation of cytokines and prostaglandins). The effect of UDC-II on discoidin receptors of chondrocytes helps to prevent structural disorders of the cartilage connective tissue. Experimental and clinical studies have shown that under the influence of standardized UDC-II, there is an increase in the proportion of regulatory CD4+ T cells, a decrease in the levels of pro-inflammatory cytokines, such as interleukin (IL) 1β, IL6, tumor necrosis factor α, CRP, prostaglandins in the blood, as well as matrix metalloproteinase 3 and NF-κB expression in cartilage. The use of UDC-II in OA leads to a significant reduction in pain, an increase in the range of joint motion, an improvement in joint function according to WOMAC and quality of life.