Abstract. Hydrogen sulfide (H 2 S) participates in multifarious physiological and pathophysiologic progresses of cancer both in vitro and in vivo.We have previously demonstrated that exogenous H 2 S promoted liver cancer cells proliferation/anti-apoptosis/angiogenesis/migration effects via amplifying the activation of NF-κB pathway. However, the effects of H 2 S on cancer cell proliferation and apoptosis are controversial and remain unclear in C6 glioma cells. The present study investigated the effects of exogenous H 2 S on cancer cells growth via activating p38 MAPK/ERK1/2-COX-2 pathways in C6 glioma cells. C6 glioma cells were treated with 400 µmol/l NaHS (a donor of H 2 S) for 24 h. The expression levels of phosphorylated (p)-p38 MAPK, total (t)-p38 MAPK, p-ERK1/2, t-ERK1/2, cyclooxygenase-2 (COX-2) and caspase-3 were measured by western blotting assay. Cell viability was detected by Cell Counting . Apoptotic cells were observed by Hoechst 33258 staining assay. Cell proliferation was directly detected under fully automatic inverted microscope. Exposure of C6 glioma cells to NaHS resulted in cell proliferation, as evidenced by an increase in cell viability. In addition, NaHS treatment reduced apoptosis, as indicated by the decreased apoptotic percentage and the cleaved caspase-3 expression. Importantly, exposure of the cells to NaHS increased the expression levels of p-p38 MAPK, p-ERK1/2 and COX-2. Notably, co-treatment of C6 glioma cells with 400 µmol/l NaHS and AOAA (an inhibitor of CBS) largely suppressed the above NaHS-induced effects. Combined treatment with NaHS and SB203580 (an inhibitor of p38 MAPK) or PD-98059 (an inhibitor of ERK1/2) resulted in the synergistic reduction of COX-2 expression and increase of caspase-3 expression, a decreased number of apoptotic cells, along with decreased cell viability. Combined treatment with NS-398 (an inhibitor of COX-2) and NaHS also resulted in the synergistic increase of caspase-3, a decreased in the number of apoptotic cells and the decrease in cell viability. The findings of the present study provide novel evidence that p38 MAPK/ERK1/2-COX-2 pathways are involved in NaHS-induced cancer cell proliferation and anti-apoptosis in C6 glioma cells.

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The effect of chemical refining process on the physicochemical characteristics and oxidative stability of perilla seed oil was investigated. We analyzed five samples corresponding to each step of the refining process (degumming, neutralization, bleaching, deodorization, and refined oil). The results indicated that the acid value (2.20–0.24 mg KOH/g) and peroxide value (4.32–1.26 mEq/kg) decreased significantly, while the saponification value (178.81–196.24 mg KOH/g) and p‐anisidine value (3.45–9.55) increased dramatically. There was no significant difference in conjugated diene, except in the degummed oil. Additionally, the refractive index did not change throughout the process. Eleven fatty acids were identified in samples, and there was no significant difference observed among them. The refining process resulted in decreases in total tocopherol content (25.0%) and total phenolic content (51.7%). Degummed, neutralized, bleached, and deodorized oils have high primary oxidation stability, whereas refined oils exhibit low secondary oxidation rates. Practical applications The present study was designed to examine the physicochemical properties of perilla seed oil at various phases of refining, as well as its bioactive compounds and oxidative stability during the process. This study provides a good reference for the industrial parameters of the refining process to obtain high‐quality products for consumers.

Determination of the full elastic constants (cij) of methane hydrates (MHs) at extreme pressure-temperature environments is essential to our understanding of the elastic, thermodynamic, and mechanical properties of methane in MH reservoirs on Earth and icy satellites in the solar system. Here, we have investigated the elastic properties of singe-crystal cubic MH-sI, hexagonal MH-II, and orthorhombic MH-III phases at high pressures in a diamond anvil cell. Brillouin light scattering measurements, together with complimentary equation of state (pressure-density) results from X-ray diffraction and methane site occupancies in MH from Raman spectroscopy, were used to derive elastic constants of MH-sI, MH-II, and MH-III phases at high pressures. Analysis of the elastic constants for MH-sI and MH-II showed intriguing similarities and differences between the phases' compressional wave velocity anisotropy and shear wave velocity anisotropy. Our results show that these high-pressure MH phases can exhibit distinct elastic, thermodynamic, and mechanical properties at relevant environments of their respective natural reservoirs. These results provide new insight into the determination of how much methane exists in MH reservoirs on Earth and on icy satellites elsewhere in the solar system and put constraints on the pressure and temperature conditions of their environment.

Summary Biochemical reactions in cells serve as the endogenous source of heat, maintaining a constant body temperature. This process requires proper control; otherwise, serious consequences can arise due to the unwanted but unavoidable responses of biological systems to heat. This review aims to present a range of responses to heat in biological systems across various spatial scales. We begin by examining the impaired thermogenesis of malignant hyperthermia in model mice and skeletal muscle cells, demonstrating that the progression of this disease is caused by a positive feedback loop between thermally driven Ca2+ signaling and thermogenesis at the subcellular scale. After we explore thermally driven force generation in both muscle and non-muscle cells, we illustrate how in vitro assays using purified proteins can reveal the heat-responsive properties of proteins and protein assemblies. Building upon these experimental findings, we propose the concept of "trans-scale thermal signaling".