Objective:To explore the effect of hydrogen sulfide (H 2S) on modulating the subunit Kir6.2 of adenosine triphosphate sensitive potassium channels via the cyclic guanosine monophosphate-dependent protein kinase (cGMP/PKG) signaling pathway in epileptic rat models. Methods:Sixty adult male SD rats were randomly divided into the following six groups (10 rats in each group) by random number table method: control, epileptic, H 2S donor, H 2S donor+epileptic, KT5823 (one inhibitor of the cyclic guanosine monophosphate-dependent protein kinase)+H 2S donor+epileptic, and glibenclamide (one inhibitor of the adenosine triphosphate sensitive potassium channels)+H 2S donor+epileptic groups. Except the control group, SD rats were intraperitoneally injected with plentylenetetrazole to make the kindling models and their behaviours were recorded including the latency period, the grade, and the duration of the first epileptic seizure according to the Racine′s standard. The waveforms of electroencephalogram (EEG) in hippocampus were also recorded during the seizure. The mRNA and protein levels of PKG and Kir6.2 in hippocampus were evaluated by Western blotting and quantitative real-time polymerase chain reaction, and the hippocampal concentrations of cGMP and phosphorylation of cyclic guanosine monophosphate-dependent protein kinase (p-PKG) were detected by enzyme linked immunosorbent assay. Results:Rats in the epileptic group showed Ⅳ-Ⅴ grade of epileptic seizure [4.500 (4.000, 4.875)], short latency period [(10.37±8.21) min] but long duration [(69.50±24.37) s] of seizure. Compared to the epileptic group, rats in the H 2S donor group showed Ⅱ-Ⅲ grade of epileptic seizure ( P=0.004), significantly longer latency period ( P<0.001), and shorter duration of seizure ( P<0.001). Compared to the H 2S donor+epileptic group, rats in the KT5823+H 2S donor+epileptic group showed Ⅲ-Ⅳ grade of epileptic seizures, significantly shorter latency period ( P<0.001), and longer duration of seizure ( P<0.001). The results of EEG showed that the wave patterns in the epileptic group were spike or sharp waves and the amplitudes were largest [(190.570±23.590) μV]. Compared with the epileptic group, amplitudes were reduced ( P<0.001) in the H 2S donor+epileptic group. PKG mRNA and PKG protein were expressed differently among all groups (PKG mRNA: n=5, H=26.714, P<0.001; PKG protein: n=5, F=30.597, P<0.001). Compared with the control group, the expression of both PKG mRNA and PKG protein was decreased (PKG mRNA: 1.000±0.001 vs 0.782±0.064, P=0.023; PKG protein: 0.550±0.037 vs 0.145±0.020, P=0.042) in the epileptic group. Besides, Kir6.2 mRNA and Kir6.2 protein were expressed differently among all groups (Kir6.2 mRNA: n=5, H=27.761, P<0.001; Kir6.2 protein: n=5, F=60.659, P<0.001). Compared with the control group, the expression of both Kir6.2 mRNA and Kir6.2 protein was decreased (Kir6.2 mRNA: 1.000±0.001 vs 0.897±0.033, P=0.004; Kir6.2 protein: 0.384±0.035 vs 0.215±0.016, P=0.024) in the epileptic group. And the concentrations of cGMP and p-PKG were decreased (cGMP: P<0.001; p-PKG: P<0.001) in the epileptic group. The results in the H 2S donor+epileptic group were up-regulated (PKG mRNA: P=0.047; PKG protein: P<0.001; Kir6.2 mRNA: P=0.011; Kir6.2 protein: P<0.001; cGMP: P<0.001; p-PKG: P<0.001) compared with the epileptic group. However, the results in the KT5823+H 2S donor+epileptic group were down-regulated (PKG mRNA: P=0.015; PKG protein: P=0.027; Kir6.2 mRNA: P=0.013; Kir6.2 protein: P=0.017; cGMP: P=0.005; p-PKG: P<0.001) compared with the H 2S donor+epileptic group. Conclusion:A possible mechanism is that H 2S prevents the epileptic seizure from modulating the subunit Kir6.2 of ATP sensitive potassium channels via the cGMP/PKG signaling pathway.

The massive accumulation of β-amyloid （Aβ） in the brain is believed to be the first pathological mechanism of Alzheimer's disease （AD）， and the accumulation is mainly resulted from the overproduction and dysfunction in the clearance. Extensive and in-depth research has been carried out on AD. In addition to the drugs which are commonly used in clinical settings to improve cognitive function， Aβ monoclonal antibody aducanumab （Aduhelm） has been successfully marketed in the US， which may delay the progress of AD. Thus， it is a potential method for the treatment of AD to target Aβ， but it is expensive， with many adverse reactions and contraindications， which hinders the clinical promotion. Traditional Chinese medicine， featuring multiple components， multiple targets， multiple pathways， and high safety， can regulate the level of Aβ deposition in the brain， alleviate neurotoxicity， and prevent and treat AD by inhibiting the production and aggregation of Aβ and promoting the clearance in the brain. Berberine， gallic acid， osthole， scutellaria barbata flavonoids， Huannao Yicong decoction and Ditantang can promote α-secretase and inhibit the activity and expression of β- and γ-secretase， thus reducing production of Aβ. Baicalein， aloe-emodin， gallic acid， and curcumin can suppress the aggregation of Aβ， promote its depolymerization， and reduce the toxic effect of Aβ on nerve cells by interacting with the hydrophobic structure of Aβ and the H bond， salt bridge， and β-sheet that mediate the aggregation of Aβ. Curcumin and resveratrol can promote the expression of triggering receptor 2 in bone marrow cells of microglia and the migration and phagocytosis of Aβ in microglia. Bilobalide， Kaixinsan and curcumin can up-regulate the expression of encephalin-degrading enzyme and insulin degrading enzyme to promote Aβ degradation， and geniposide， dihydrotanshinone， dihydroartemisinin， and curcumin can degrade Aβ in cells by activating normal autophagy or inhibiting abnormal autophagy. Cycloastragenol， Danggui Shaoyaosan， Yizhi Fangdai formula and Linggui Zhugan decoction can promote the outflow of Aβ and inhibit the inflow of Aβ by improving the integrity and permeability of the blood-brain barrier （BBB）. Yizhi Fangdai formula and Xueshuantong can promote the polarization of aquaporin 4（AQP4）， allow Aβ to be cleared through the lymphatic system， and reduce the aggregation of Aβ in the brain， thereby relieving or preventing nerve cell damage and improving cognitive function. The above summary aims to provide more sufficient evidence and ideas for the clinical treatment of AD with traditional Chinese medicine.

Colorectal cancer (CRC), a malignant tumor worldwide consists of microsatellite instability (MSI) and stable (MSS) phenotypes. Although SHP2 is a hopeful target for cancer therapy, its relationship with innate immunosuppression remains elusive. To address that, single-cell RNA sequencing was performed to explore the role of SHP2 in all cell types of tumor microenvironment (TME) from murine MC38 xenografts. Intratumoral cells were found to be functionally heterogeneous and responded significantly to SHP099, a SHP2 allosteric inhibitor. The malignant evolution of tumor cells was remarkably arrested by SHP099. Mechanistically, STING-TBK1-IRF3-mediated type I interferon signaling was highly activated by SHP099 in infiltrated myeloid cells. Notably, CRC patients with MSS phenotype exhibited greater macrophage infiltration and more potent SHP2 phosphorylation in CD68⁺ macrophages than MSI-high phenotypes, suggesting the potential role of macrophagic SHP2 in TME. Collectively, our data reveals a mechanism of innate immunosuppression mediated by SHP2, suggesting that SHP2 is a promising target for colon cancer immunotherapy.