An herbal medicine, Go-sha-jinki-gan (GJG), increases muscle weight in severe muscle dystrophy model mice

The potential of traditional herbal active ingredients in the treatment of sarcopenia animal models: focus on therapeutic effects and mechanisms

Sarcopenia is a major global public health problem that harms individual physical function. In 2018, the European Working Group on Sarcopenia in the Elderly 2 classified sarcopenia into primary and secondary sarcopenia. However, information on the pathogenesis and effective treatment of primary and secondary sarcopenia is limited. Traditional herbal active ingredients have biological activities that promote skeletal muscle health, showing potential preventive and therapeutic effects on sarcopenia. Therefore, this narrative review aims to provide a comprehensive overview of global traditional herbal active ingredients' beneficial therapeutic effects and molecular mechanisms on sarcopenia-related animal models. For this purpose, we conducted a literature search in three databases, PubMed, Web of Science, and Embase, consistent with the review objectives. After the screening, 12 animal studies met the review themes. The review results showed that the pathological mechanisms in sarcopenia-related animal models include imbalanced protein metabolism, oxidative stress, inflammation, apoptosis, insulin resistance, endoplasmic reticulum stress, impaired mitochondrial biogenesis, and autophagy-lysosome system aggravation. Eleven traditional herbal active ingredients exerted positive anti-sarcopenic effects by ameliorating these pathological mechanisms. This narrative review will provide meaningful insight into future studies regarding traditional herbal active ingredients for treating sarcopenia.

The Japan Frailty Scale is a promising screening test for frailty and pre-frailty in Japanese elderly people

Frailty is one of the most important problems in a super-aged society. It is necessary to identify frailty quickly and easily at the bedside. We developed a simple patient-reported frailty screening scale, the Japan Frailty Scale (JFS), based on the aging concept of Kampo medicine. Eight candidate questions were prepared by Kampo medicine experts, and a simple prediction model was created in the development cohort (n=434) and externally validated in an independent validation cohort (n=276). The physical indicators and questionnaires associated with frailty were also comprehensively evaluated. The reference standard for frailty or pre-frailty was determined based on the Kihon checklist. In the development cohort, four questions, nocturia (0-2), lumbago (0-2), cold sensitivity (0-2), exhaustion (0-4), and age (0-1) were selected by multivariable logistic regression analysis. The total JFS score is 0-11. Receiver-operating characteristic curve analysis of the JFS for identifying frailty status showed moderately good discrimination (area under the curve (AUC) =0.78, 95% confidence interval (CI): 0.73-0.82). At the JFS cutoff value of 3/4 for frailty or pre-frailty, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.9%, 53.3%, 62.8%, and 81.7%, respectively. External validation of the JFS showed moderately good discrimination (AUC=0.76, 95% CI: 0.70-0.81). The sensitivity, specificity, PPV, and NPV were 79.9%, 61.4%, 69.3%, and 73.7%, respectively. These results indicate that the JFS is a promising patient-reported clinical scale for early identification of pre-frail/frail patients at the bedside in primary care.

Goshajinkigan, a Traditional Japanese Medicine, Suppresses Voltage-Gated Sodium Channel Nav1.4 Currents in C2C12 Cells

Goshajinkigan (GJG) is a traditional Japanese Kampo medicine used clinically to treat muscle pain in Japan. However, its underlying mechanism remains unclear. Since voltage-gated sodium channel (Nav) 1.4 is involved in skeletal muscle contraction, we investigated the possibility that GJG may affect Nav1.4 currents. By using an electrophysiological technique on skeletal muscle cell line C2C12, we found that GJG suppresses Nav1.4 currents in C2C12 cells. It is suggested that GJG may improve skeletal muscle stiffness or cramps by inhibiting abnormal Nav1.4 excitation. GJG may act as a Nav1.4 blocker and may be useful to treat muscle stiffness and clamps as well as easing the pain.

Juzentaihoto Suppresses Muscle Atrophy in Streptozotocin-Induced Diabetic Mice

In diabetic patients, skeletal muscle atrophy occurs due to increased oxidative stress and inflammation. Skeletal muscle atrophy reduces the QOL of patients and worsens life prognosis. Therefore, development of preventive therapy for muscle atrophy in hyperglycemic state is eagerly awaited. Juzentaihoto is a medicinal herb that has a function to supplement physical strength, and it is expected to prevent muscle atrophy. To determine the preventive effect of juzentaihoto on muscle atrophy in hyperglycemic state, streptozotocin (STZ) was administered to induce diabetes in mice and the preventive effect of juzentaihoto was evaluated. Mice that received juzentaihoto extract (JTT) showed that the decrease in muscle fiber cross-sectional area in the gastrocnemius muscle was reversed. Additionally, the expression level of tumor necrosis factor α (TNF-α), an inflammatory cytokine, in serum decreased, and that of ubiquitin ligase (atrogin-1, muscle RING-finger protein-1) mRNA in skeletal muscle decreased. An anti-inflammatory cytokine interleukin-10 showed increased levels in the serum and increased levels in spleen cell culture supernatant collected from mice that received JTT. JTT had no effect on the blood glucose level. These results suggest that prophylactic administration of JTT to STZ-induced diabetic mice affects immune cells such as in spleen, causing an anti-inflammatory effect and inhibiting excessive activation of the ubiquitin-proteasome system, to reverse muscle atrophy.

"Of Mice and Measures": A Project to Improve How We Advance Duchenne Muscular Dystrophy Therapies to the Clinic

A new line of dystrophic mdx mice on the DBA/2J (D2) background has emerged as a candidate to study the efficacy of therapeutic approaches for Duchenne muscular dystrophy (DMD). These mice harbor genetic polymorphisms that appear to increase the severity of the dystropathology, with disease modifiers that also occur in DMD patients, making them attractive for efficacy studies and drug development. This workshop aimed at collecting and consolidating available data on the pathological features and the natural history of these new D2/mdx mice, for comparison with classic mdx mice and controls, and to identify gaps in information and their potential value. The overall aim is to establish guidance on how to best use the D2/mdx mouse model in preclinical studies.

Juzentaihoto hot water extract alleviates muscle atrophy and improves motor function in streptozotocin-induced diabetic oxidative stress mice

A decrease in skeletal muscle mass and motor function occurs in diabetic patients. In type 1 diabetic patients, in particular, fast-type fiber-dominated muscle atrophy occurs due to increased oxidative stress and inflammation. Juzentaihoto is a herbal medicine that has been found to be effective in reducing oxidative stress. In this study, juzentaihoto hot water extract (JTT) was administered prophylactically to mice with diabetic oxidative stress, which was induced by an injection of streptozotocin, and the effects on skeletal muscle mass, motor function, and antioxidant activity were evaluated. In mice that were administered JTT, skeletal muscle atrophy and loss of motor function were suppressed. Additionally, the administration of JTT increased the mRNA expression level of Sirt1 and the activity of superoxide dismutase in the gastrocnemius. In addition to skeletal muscle atrophy, atrophy of the liver, spleen and thymus gland, and kidney hypertrophy were also suppressed. Furthermore, in order to evaluate the antioxidant activity of 10 constituent crude drugs that comprise juzentaihoto, Sirt1 transcriptional activity in C2C12 cells was evaluated. The Sirt1 transcriptional activity was increased by Cinnamomi Cortex, Astragali Radix, and Glycyrrhizae Radix extracts. These three constituent crude drugs play an important function in the antioxidant action of juzentaihoto, suggesting that juzentaihoto can prevent muscle atrophy by decreasing oxidative stress.