Insulin-Like Growth Factor 1 Receptor Deficiency Alleviates Angiotensin II-Induced Cardiac Fibrosis Through the Protein Kinase B/Extracellular Signal-Regulated Kinase/Nuclear Factor-κB Pathway.

Background The renin-angiotensin system plays a crucial role in the development of heart failure, and Ang II (angiotensin II) acts as the critical effector of the renin-angiotensin system in regulating cardiac fibrosis. However, the mechanisms of cardiac fibrosis are complex and still not fully understood. IGF1R (insulin-like growth factor 1 receptor) has multiple functions in maintaining cardiovascular homeostasis, and low-dose IGF1 treatment is effective in relieving Ang II-induced cardiac fibrosis. Here, we aimed to investigate the molecular mechanism of IGF1R in Ang II-induced cardiac fibrosis. Methods and Results Using primary mouse cardiac microvascular endothelial cells and fibroblasts, in vitro experiments were performed. Using C57BL/6J mice and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9)-mediated IGF1R heterozygous knockout (Igf1r+/-) mice, cardiac fibrosis mouse models were induced by Ang II for 2 weeks. The expression of IGF1R was examined by quantitative reverse transcription polymerase chain reaction, immunohistochemistry, and Western blot. Mice heart histologic changes were evaluated using Masson and picro sirius red staining. Fibrotic markers and signal molecules indicating the function of the Akt (protein kinase B)/ERK (extracellular signal-regulated kinase)/nuclear factor-κB pathway were detected using quantitative reverse transcription polymerase chain reaction and Western blot. RNA sequencing was used to explore IGF1R-mediated target genes in the hearts of mice, and the association of IGF1R and G-protein-coupled receptor kinase 5 was identified by coimmunoprecipitation. More important, blocking IGF1R signaling significantly suppressed endothelial-mesenchymal transition in primary mouse cardiac microvascular endothelial cells and mice in response to transforming growth factor-ß1 or Ang II, respectively. Deficiency or inhibition of IGF1R signaling remarkably attenuated Ang II-induced cardiac fibrosis in primary mouse cardiac fibroblasts and mice. We further observed that the patients with heart failure exhibited higher blood levels of IGF1 and IGF1R than healthy individuals. Moreover, Ang II treatment significantly increased cardiac IGF1R in wild type mice but led to a slight downregulation in Igf1r+/- mice. Interestingly, IGF1R deficiency significantly alleviated cardiac fibrosis in Ang II-treated mice. Mechanistically, the phosphorylation level of Akt and ERK was upregulated in Ang II-treated mice, whereas blocking IGF1R signaling in mice inhibited these changes of Akt and ERK phosphorylation. Concurrently, phosphorylated p65 of nuclear factor-κB exhibited similar alterations in the corresponding group of mice. Intriguingly, IGF1R directly interacted with G-protein-coupled receptor kinase 5, and this association decreased ≈50% in Igf1r+/- mice. In addition, Grk5 deletion downregulated expression of the Akt/ERK/nuclear factor-κB signaling pathway in primary mouse cardiac fibroblasts. Conclusions IGF1R signaling deficiency alleviates Ang II-induced cardiac fibrosis, at least partially through inhibiting endothelial-mesenchymal transition via the Akt/ERK/nuclear factor-κB pathway. Interestingly, G-protein-coupled receptor kinase 5 associates with IGF1R signaling directly, and it concurrently acts as an IGF1R downstream effector. This study suggests the promising potential of IGF1R as a therapeutic target for cardiac fibrosis.

Exogenous hydrogen sulfide promotes cell proliferation and differentiation by modulating autophagy in human keratinocytes.

The effects and the underlying mechanisms of hydrogen sulfide (H2S) on keratinocyte proliferation and differentiation are still less known. In the current study, we investigated the effects and the underlying mechanisms of exogenous H2S on keratinocyte proliferation and differentiation. Human keratinocytes (HaCaT cells) were treated with various concentrations (0.05, 0.25, 0.5 and 1 mM) of sodium hydrosulfide (NaHS, a donor of H2S) for 24 h. A CCK-8 assay was used to assess cell viability. Western blot analysis was performed to determine the expression levels of proteins associated with differentiation and autophagy. Transmission electron microscopy was performed to observe autophagic vacuoles, and flow cytometry was applied to evaluate apoptosis. NaHS promoted the viability, induced the differentiation, and enhanced autophagic activity in a dose-dependent manner in HaCaT cells but had no effect on cell apoptosis. Blockage of autophagy by ATG5 siRNA inhibited NaHS-induced cell proliferation and differentiation. The current study demonstrated that autophagy in response to exogenous H2S treatment promoted keratinocyte proliferation and differentiation. Our results provide additional insights into the potential role of autophagy in keratinocyte proliferation and differentiation.

Antioxidant and anti-aging activities of mycelial polysaccharides from Lepista sordida.

The intracellular polysaccharides (CLSP) were extracted from Lepista sordida mycelium in submerged culture followed by concentration and ethanol precipitation. The antioxidant activities of CLSP were evaluated both in vitro and in vivo. In vitro antioxidant assay, CLSP had noticeable scavenging activities on superoxide anion, hydroxyl radical and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical. For antioxidant testing in vivo, different doses of CLSP were orally administrated over a period of 6 weeks in a D-galactose induced aged mice model. As results, CLSP significantly inhibited the formation of malondialdehyde (MDA) and raised the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in mice brains and serums in a dose-dependent manner. The results provide a reference for large-scale production of CLSP by submerged fermentation and suggested that CLSP had potent antioxidant activity and could be explored as a potential dietary supplement to retard aging and attenuate age-related diseases in humans.

Factors contributing to the high prevalence of multidrug-resistant tuberculosis: a study from China.

BACKGROUND: The rapid spread of multidrug-resistant tuberculosis (MDR-TB) has attracted global concerns. This study aimed to identify factors contributing to the high prevalence of MDR-TB in China's Heilongjiang province. METHODS: A cross-sectional survey following the WHO/International Union Against Tuberculosis and Lung Disease guidelines was conducted with consecutive recruitment of patients with TB in 30 counties selected at random in Heilongjiang in 2004. A total of 1995 patients were tested for MDR-TB. Factors associated with MDR-TB were identified through multilevel models and traditional logistic regression analysis, along with in-depth interviews with nine patients, five healthcare managers and four doctors. RESULTS: 241 patients (12%) were identified with MDR-TB. The retreatment patients were 5.48 times (95% CI 4.04 to 7.44) more likely to have MDR-TB than newly diagnosed patients. The patients who were treated with isoniazid and rifampin for >180 days were 4.82 times (95% CI 2.97 to 7.81) more likely to develop MDR-TB than those treated <180 days. Age and delay in initiating TB treatment were associated with MDR-TB. Financial burden, poor knowledge and side effects of TB treatment were perceived by the interviewees as influencing factors. Lack of coordination of services, unsatisfactory supervision of treatment and infection control jeopardised the control of MDR-TB. CONCLUSIONS: Inappropriate treatment is the most important influencing factor of MDR-TB. Increasing people's awareness of TB, early detection and appropriate treatment of patients with TB should become a priority, which requires strong commitment and collaboration among health organisations and greater compliance with TB treatment guidelines by service providers and patients.

[Study on the efficacy and safety of short-term treatment including fluoroquinolones anti-tuberculosis drugs for rifampicin resistant pulmonary tuberculosis].

OBJECTIVE: To evaluate the efficacy and safety of short-term treatment including fluoroquinolones anti-tuberculosis drugs for rifampicin resistant pulmonary tuberculosis (TB) in those areas carrying out the 'TB control project'. METHODS: TB cases involved in this study were from TB drug resistance surveillance in Heilongjiang province, Zhejiang province and Shenzhen city from 2004 to 2006. TB cases with rifampicin resistant were randomly divided into the treatment group (including fluoroquinolones anti-tuberculosis drugs group) and the control group (re-treatment regimen group). The treatment group was treated with 3RFT AM Ofx Pto PAS-INH/5RFT Ofx Pto PAS-INH while the control group was treated with 3 H3R3Z3E3S3/5 H3R3E3. Efficacy of short-term treatment was analyzed by per-protocol analysis (PP analysis) and intention-to-treat analysis (ITT analysis) while drug adverse reactions was also observed. RESULTS: (1) 154 patients with rifampicin resistant pulmonary tuberculosis were recruited among them, 25 (16.2%) were only resistant to rifampicin, 114 (74.0%) to MDR-TB and 15 (9.8%) to others (resistant R+S, resistant R+E and resistant R+E+S). 114 TB cases completed the full course of treatment,with 71 in the treatment group and 43 in the control group. (2) Sputum negative conversion rate of the treatment group and the control group were 78.9% and 65.1% (chi2CMH = 4.558, P = 0.011) respectively, by per-protocol analysis. Sputum negative conversion rate of the treatment group and the control group were 65.9% and 40.6% (chi2CMH = 0.272, P = 0.001) respectively, by intention-to-treat analysis. The sputum negative conversion rate of the treatment group was higher than in the control group when treating rifampicin resistant pulmonary tuberculosis and MDR-TB patients. (3) Three patients withdrew in each of the two groups because of adverse effects to the drugs. Rates of adverse reaction to drugs appeared to be 23.9% (17/71) and 18.6% (8/43) in the treatment and in the control groups, with no statistically significant difference between the two groups. CONCLUSION: The efficacy of treatment including fluoroquinolones anti-tuberculosis drugs group seemed better than the re-treatment regimen group in treating patients with rifampicin resistant pulmonary tuberculosis and those MDR-TB patients.

[Effects of two treatment regimens for drug-resistant tuberculosis in tuberculosis control project areas: a comparative study].

OBJECTIVES: To search for an ideal therapeutic regimen for multidrug resistant tuberculosis conforming to the situation of China. METHODS: One hundred and fifty-four patients with rifampin-resistant tuberculosis, 114 multi-drug resistant (MDR-TB) and 40 resistant to other drugs, in Heilongjiang, Zhejiang, and Shenzhen, 107 males and 47 females, aged 39 (19-77), were randomly divided into 2 groups: 85 patients in the group of drug-resistant regimen, 3RFT AM Ofx Pto PAS-INH/5RFT Ofx Pto PAS-INH regimen, including rifapentine (RFT), amikacin (Am), ofloxacin (Ofx), protionamide (Pto), para-aminosalicylic acid-isoniazid (PAS-INH) for 3 months and then RFT, Ofx, Pto, and PAS-INH for 5 months, and 69 in the retreatment regimen group undergoing 3 H3R3Z3E3S3/5 H3R3E3, including isoniazid (H), rifampin (R), pyrazinamide (Z), ethambutol (E), and streptomycin (S) for 3 months and then H, R, and E for 5 months. Sputum smear was checked and the sputum smear conversion rate was calculated as an effective treatment indicator 3, 6, and 8 months later. RESULTS: One hundred and fourteen of the 154 patients were treated for a good 8 months. The sputum smear conversion rate 8 months after treatment of the drug-resistant regimen group was 65.9% (56/85), significantly higher than that of the retreatment regimen group [40.6% (28/69), chi2 = 9.834, P = 0.002]. Eighty-five of the 114 MDR-TB patients had been treated for a good 8 months with a sputum smear conversion rate of 61.8% (42/68), significantly higher than that of the retreatment regimen group [39.1% (18/46), chi2 = 5.638, P = 0.018]. Sputum smear conversion at the end of the 8th month was related to age, course of disease, therapeutic regimen, and the type of drug-resistance (all P < 0.05). The side-effect rate of the drug-resistant regimen group was 23.9% (17/71), higher than that of the retreatment regimen group [18.6% (8/43)], but not significantly (chi2 = 0.446, P = 0.504). CONCLUSION: The drug-resistant regimen recommended above is more effective than the retreatment regimen and should be considered in the areas where the WHO guideline fails to be followed or drug sensitivity test (DST) cannot be conducted and adjusted according to the results of DST and treatment.