ALKBH5-mediated m6A modification of IL-11 drives macrophage-to-myofibroblast transition and pathological cardiac fibrosis in mice.

Cardiac macrophage contributes to the development of cardiac fibrosis, but factors that regulate cardiac macrophages transition and activation during this process remains elusive. Here we show, by single-cell transcriptomics, lineage tracing and parabiosis, that cardiac macrophages from circulating monocytes preferentially commit to macrophage-to-myofibroblast transition (MMT) under angiotensin II (Ang II)-induced hypertension, with accompanying increased expression of the RNA N6-methyladenosine demethylases, ALKBH5. Meanwhile, macrophage-specific knockout of ALKBH5 inhibits Ang II-induced MMT, and subsequently ameliorates cardiac fibrosis and dysfunction. Mechanistically, RNA immunoprecipitation sequencing identifies interlukin-11 (IL-11) mRNA as a target for ALKBH5-mediated m6A demethylation, leading to increased IL-11 mRNA stability and protein levels. By contrast, overexpression of IL11 in circulating macrophages reverses the phenotype in ALKBH5-deficient mice and macrophage. Lastly, targeted delivery of ALKBH5 or IL-11 receptor α (IL11RA1) siRNA to monocytes/macrophages attenuates MMT and cardiac fibrosis under hypertensive stress. Our results thus suggest that the ALKBH5/IL-11/IL11RA1/MMT axis alters cardiac macrophage and contributes to hypertensive cardiac fibrosis and dysfunction in mice, and thereby identify potential targets for cardiac fibrosis therapy in patients.

Total Flavones of Rhododendron simsii Planch Flower Protect against Cerebral Ischemia-Reperfusion Injury via the Mechanism of Cystathionine-γ-Lyase-Produced H2S.

Total flavones of Rhododendron simsii Planch flower (TFR) have a significant protective effect against cerebral ischemia-reperfusion injury. However, its mechanism is unclear. This study investigated the protection of TFR against cerebral ischemia-reperfusion injury via cystathionine-γ-lyase- (CSE-) produced H2S mechanism. CSE-/- mice and CSE-siRNA-transfected rat were used. Relaxation of cerebral basilar artery (CBA), H2S, and CSE mRNA were measured. TFR significantly inhibited cerebral ischemia-reperfusion-induced abnormal neurological symptom and cerebral infarct in the normal rats and the CSE+/+ mice, but not in the CSE-/- mice, and the inhibition was markedly attenuated in CSE-siRNA-transfected rat; TFR elicited a significant vasorelaxation in rat CBA, and the relaxation was markedly attenuated by removal of endothelium or CSE-siRNA transfection or coapplication of NO synthase inhibitor L-NAME and PGI2 synthase inhibitor Indo. CSE inhibitor PPG drastically inhibited TFR-evoked vasodilatation resistant to L-NAME and Indo in endothelium-intact rat CBA. TFR significantly increased CSE mRNA expression in rat CBA endothelial cells and H2S production in rat endothelium-intact CBA. The increase of H2S production resistant to L-NAME and Indo was abolished by PPG. Our data indicate that TFR has a protective effect against the cerebral ischemia-reperfusion injury via CSE-produced H2S and endothelial NO and/or PGI2 to relax the cerebral artery.

[Protective effects of perfluorocarbon combined with ligustrazine against lung ischemia-reperfusion injury in rats].

OBJECTIVE: To investigate the effects of perfluorocarbon and ligustrazine in protecting the lungs against ischemia-reperfusion injury in rats. METHDS: Forty SD rats with ischemia-reperfusion lung injury were randomized equally into control, ligustrazine, perfluorocarbon, and perfluorocarbon plus ligustrazine groups and received the corresponding treatment via the tail vein 5 min before reperfusion. The lung tissues were harvested and the levels of malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and tumor necrosis factor-α (TNF-α) were detected 3 h after reperfusion. The pathological changes and pathological scores of the lung tissues were analyzed. RESULTS: MDA and MPO levels were significantly lower and SOD activities significantly higher in the lung tissues in the 3 treatment groups than in the control group (P<0.05). The rats in the combined treatment group showed a significantly lower MPO level and a significantly higher SOD activity than those treated with ligustrazine or perfluorocarbon alone (P<0.05). No significant difference was found in TNF-α levels in the lung tissues among the 4 groups (P>0.05). The lung tissues in the control group showed obvious edema and exudation, and the tissues in ligustrazine and perfluorocarbon groups showed no edema but with a few red blood cells and exudation; no edema was found in the combined treatment group with only a small amount of exudation. The pathological scores differed significantly among the 4 groups. CONCLUSION: Perfluorocarbon and ligustrazine, especially in combined use, can promote endogenous oxygen free radical scavenging, decrease peripheral blood proinflammatory cytokines, and inhibit neutrophils filtration in the lungs of rats with ischemia/reperfusion lung injury.

Panax ginseng inhibits intestinal absorption of toxic Aconitum carmichaeli alkaloids in Vitro.

OBJECTIVE: To evaluate the rationality and compatibility of Shenfu Formula (, SFF), a typical Chinese medicine (CM) comprised of Panax ginseng and Aconitum carmichaeli. METHODS: Caco-2 cells were used to study the permeability of Aconitum carmichaeli marker compounds when the CM preparation was combined with Panax ginseng. P-glycoprotein (P-gp) activity and protein as well as multidrug resistance 1 (MDR1) mRNA were analyzed with rhodamine123 efflflux, western blot and real time quantitative polymerase chain reaction. RESULTS: Aconitine (AC), mesaconitine (MA), hypaconitine (HA) and fifive other active alkaloids in Aconitum carmichaeli were selected as marker compounds. Panax ginseng inhibited intestinal absorption of highly toxic AC, MA and HA from Aconitum carmichaeli in Caco-2 cells. P-gp and breast cancer resistance protein (BCRP) were observed to be involved in AC, MA and HA efflflux. Panax ginseng induced P-gp activity in Caco-2 cells via increased MDR1/P-gp expression. Thus, Panax ginseng facilitated P-gp-mediated efflflux of toxic Aconitum carmichaeli alkaloids and restricted their intestinal absorption without inflfluencing other active components. CONCLUSION: Future studies to elucidate mechanism of reduced toxicity of Aconitum carmichaeli when combined with Panax ginseng will guide future formula optimization.

[Comparison of single intubating dose and continuous infusion of rocuronium in prolonged gynecologic laparoscopic surgery].

OBJECTIVE: To compare the cardiorespiratory factors and surgical conditions during total intravenous anesthesia for prolonged laparoscopic pelvic surgery with or without supplemental muscle relaxants. METHODS: Forty female ASA I or II patients undergoing laparoscopic pelvic surgeries were randomized into two groups A and B, both with standardized anesthesia via a intravenous bolus injection of rocuronium (0.6 mg/kg). The patients in group B received continuous rocuronium infusion upon observation of one TOF twitch response with the T1 value maintained within 0-10% and rocuronium withdrawal at 20 to 30 min before the completion of the surgery. The patients in group A received no supplemental muscle relaxants. The cardiorespiratory parameters were measured during the operation. The respiratory system compliance (Ceff rs) was calculated as the quotient of the tidal volume (VT) and peak inspiratory pressure (PIP), and the operative conditions were graded by the operating gynecologist. RESULTS: The cardiorespiratory parameters significant increased and Ceff rs decreased after pneumoperitoneum, but no significant differences were found between the two groups. The surgical conditions were also comparable between the two groups, but the duration of intubation and the operating time were significantly shorter in the group A. CONCLUSION: Pneumoperitoneum severely affects the cardiorespiratory parameters during laparoscopy, which can not be lessened by neuromuscular block agents. A single intubating dose of rocuronium can suffice the requirement of prolonged gynecologic laparoscopic surgery.