[The effect of different types of exercise on the intestinal mechanical barrier and related regulatory factors in type 2 diabetic mice].

The aim of this study was to investigate the effects of different types of exercise on intestinal mechanical barrier and related regulatory factors in mice with type 2 diabetes mellitus (T2DM). The model was established by high-fat diet feeding and intraperitoneal injection of streptozocin (STZ). The mice were divided into control group, model group (free exercise), resistance exercise group (tail load-bearing ladder climbing, 5 times a week), aerobic exercise group (non-load-bearing platform running, 5 times a week at a speed of 10-15 m/min), and combined exercise group (aerobic exercise was performed on the first, third and fifth days of each week, and resistance exercise on the second and fourth days of each week). After 8 weeks of intervention, the serum lipid levels and inflammatory cytokines were measured by corresponding kits. The pathological changes of ileum were detected by HE and PAS staining. The mRNA and protein expression levels of tight junction-related proteins were detected by real-time qPCR and Western blot, respectively. Moreover, the protein expression levels of hypoxia inducible factor-1α (HIF-1α) and myosin light chain kinase (MLCK) were detected by Western blot. The results showed that all three types of exercise decreased blood glucose and body weight compared to the model group. Aerobic exercise and combined exercise decreased serum lipid (triglycerides and total cholesterol) levels, up-regulated the expression levels of ileal tight junction-related proteins and HIF-1α, improved the intestinal alkaline phosphatase (AKP) activity, reduced serum lipopolysaccharide (LPS), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and diamine oxidase (DAO) levels, and down-regulated MLCK protein expression level. These results suggest that all three types of exercise can reduce blood glucose and body weight of T2DM mice, and aerobic exercise and combined exercise can restore the damaged intestinal mechanical barrier by a mechanism involving HIF-1α-MLCK pathway.

Vaccarin enhances intestinal barrier function in type 2 diabetic mice.

AIMS: Hyperglycemia and insulin resistance drive intestinal barrier dysfunction in type 2 diabetes (T2DM). Vaccarin, the main active component in the semen of traditional Chinese medicine Vaccaria has a definite effect on T2DM mice. The purpose of this study was to investigate whether vaccarin can enhance the intestinal barrier function in T2DM. MAIN METHODS: The T2DM mice model was established by streptozocin and high-fat diet. Vaccarin at a dose of 1 mg/kg/day was administered. We evaluated the effects of vaccarin on gut microbiota and intestinal barrier function by 16S rRNA sequencing, Western blot, quantitative fluorescent PCR (qPCR), and morphological observation. Moreover, we constructed a single layer of the human intestinal epithelium model to determine the effect of vaccarin in vitro. RESULTS: The experimental results showed that vaccarin alleviated inflammatory mediators in serum and intestinal tissue of mice (P < 0.05), which may depend on the improvement of tight junctions and gut microbiota (P < 0.05). Activation of extracellular regulated protein kinases (Erk1/2) stimulated myosin light chain kinase (MLCK). By inhibiting ERK expression (P < 0.05), vaccarin had similar effects to ERK inhibitors. In addition, the regulation of tight junction barriers also involved the abovementioned pathways in vivo. CONCLUSION: Vaccarin could protect the intestinal barrier by inhibiting the ERK/MLCK signaling pathway and modulate the composition of the microbiota. These results suggested that vaccarin may be an effective candidate for improving intestinal barrier changes in T2DM.

1,25(OH)2 D3 attenuates sleep disturbance in mouse models of Lewis lung cancer, in silico and in vivo.

Many clinical studies have reported that patients diagnosed with cancer will suffer from sleep disturbance during their clinical process, especially among lung cancer patients, and this effect will not easily subside. 1,25-dihydroxy-vitamin-D3 [1,25(OH)2 D3 ], the activated form of vitamin D, can participate in neuronal differentiation and prevent damage to the nervous system. However, little is known about the potential therapeutic effects of cancer-related psychiatric symptoms. In light of this, we hypothesized that a low circulating level of vitamin D was related to sleep quality in the presence of a tumor, 1,25(OH)2 D3 may be an effective way to ameliorate sleep disturbance and neurochemical alterations along with the cancer progress. Male C57BL/6 mice were implanted with intracranial transmitters to monitor electroencephalogram and were subcutaneously inoculated with Lewis lung cancer cells. The results demonstrated that on Days 19-20, tumor-bearing mice displayed fragmented sleep, shortened wake phase, prolonged sleep in the non-rapid eye movement phase, and the levels of vitamin D-associated genes in the brain had changed a lot compared to control mice. Importantly, 1,25(OH)2 D3 treatment really effectively saved the sleep quality of tumor-bearing mice. We further explored and confirmed that 1,25(OH)2 D3 repressed tumor-induced neuroinflammation (IL-1ß, TNF-α, IL-6, IL-10, IFN-γ, and IL-2), enhanced neurotrophic factors (brain-derived neurotrophic factor [BDNF], glialcellline-derived neurotrophic factor) and 5-HT system in the hippocampus, hypothalamus or cortex. A molecular docking approah manifested the ability of 1,25(OH)2 D3 to affect the activity of tryptophan hydroxylase 2 and BDNF. Together, our results suggested that 1,25(OH)2 D3 treatment may attenuate sleep disturbance in Lewis lung cancer-bearing mice, and become a promising strategy for treating cancer symptom clusters to ameliorate the quality of life of patients with cancer.