The total flavonoids from ethanol extract of the aerial part of Ziziphora clinopodioides Lam. (Lamlaceae) (Xintahua) showed protective activities against rat acute myocardial ischemia in rats. This study aims to isolate acacetin, a flavonoid, from the aerial part of Z. clinopodioides, to develop an HPLC method for its detection, and to evaluate its protective effects on neonatal rat cardiomyocytes. Sephadex LH-20 silicagel and pillar layer chromatography silica gel were applied for the isolation and purification of acacetin and its structure was elucidated on the basis of 1H and 13C NMR spectroscopy. The content of acacetin in Z. clinopodioides collected from three different origins was determined by HPLC. The neonatal rat cardiomyocytes were isolated and cultured in vitro to establish a hypoxia/reoxygenation injury model. The viability of cardiomyocytes was measured by the MTT method. Changes of malondialdehyde (MDA) content in the medium were also determined. The acacetin content in various batches of Z. clinopodioides ranged from 45.50 to 47.41 μg/g. Acacetin of 25, 10, 5 μg/mL significantly decreased the MDA content in a model of hypoxia/reoxygenation injury (P < 0.001, P < 0.001 and P = 0.033, respectively). Acacetin protects neonatal cardiomyocytes from the damage induced by hypoxia/reoxygenation stress through reduction of lipid peroxidation and enhancement of the antioxidant activity.

Ischemic heart disease is a leading cause of mortality and morbidity worldwide. We previously demonstrated that acacetin protects against myocardial ischemia reperfusion injury in rats, although the underlying mechanism remains to be elucidated. In the present study, we investigated the effects of acacetin on autophagy during hypoxia/reoxygenation (H/R) injury by exposing H9c2 myocardial cells to H/R with or without acacetin pretreatment during hypoxia. Our results show that acacetin significantly increased cell viability in a dose-dependent manner, enhanced antioxidant capacity, and suppressed protein apoptosis of rat cardiomyocytes H9c2 cells following H/R injury. In addition, lentiviral infection of H9c2 cardiomyocytes revealed that acacetin pretreatment significantly enhanced the fluorescence intensity of autophagy proteins Beclin 1, LC3-II, and p62. These results indicate that acacetin protected H9c2 cardiomyocytes from H/R damage by enhancing autophagy. Moreover, we found that application of acacetin increased activation of the PI3K/Akt signaling pathway, whereas cotreatment with the PI3K inhibitor LY294002 reversed the inhibition of apoptosis and autophagy induced by acacetin. In conclusion, acacetin mitigated H/R injury by promoting autophagy through activating the PI3K/Akt/mTOR signaling pathway.

Background: Ziziphora bungeana Juz. is a folk medicine from the Xinjiang Uygur Autonomous Region. The herb or the aerial parts of it have been used to medicinally treat cardiovascular diseases. Flavonoids are the main pharmacologically active ingredients in Z. bungeana. Identification of the tissue-specific distribution of flavonoids in Z. bungeana is crucial for effective and sustainable medicinal use of the plant. Furthermore, understanding of the biosynthesis pathways of these flavonoids in Z. bungeana is of great biological significance. Methods: The flavonoids from different tissues of Z. bungeana were identified using liquid chromatography-tandem mass spectrometry (LC–MS/MS). The full-length transcriptome of Z. bungeana was determined using a strategy based on a combination of Illumina and PacBio sequencing techniques. The functions of differentially expressed unigenes were predicted using bioinformatics methods and further investigated by real-time quantitative PCR and phylogenetic relationship analysis. Results: Among the 12 major flavonoid components identified from Z. bungeana extracts, linarin was the most abundant component. Nine flavonoids were identified as characteristic components of specific tissues. Transcriptome profiling and bioinformatic analysis revealed that 18 genes were putatively involved in flavonoid biosynthesis. The gene expression and phylogenetic analysis results indicated that ZbPALs, Zb4CL3, ZbCHS1, and ZbCHI1 may be involved in the biosynthesis of the main flavonoid intermediate. ZbFNSII, ZbANS, and ZbFLS may be involved in the biosynthesis of flavones, anthocyanins, and flavonols, respectively. A map of the biosynthesis pathways of the 12 major flavonoids in Z. bungeana is proposed. Conclusions: The chemical constituent analysis revealed the compositions of 9 characteristic flavonoids in different tissues of Z. bungeana. Linarin can be hydrolysed into acacetin to exert a pharmaceutical role. Apigenin-7-O-rutinoside is hypothesised to be the precursor of linarin in Z. bungeana. There was greater content of linarin in the aerial parts of the plant than in the whole herb, which provides a theoretical basis for using the aerial parts of Z. bungeana for medicine. These results provide a valuable reference for further research on the flavonoid biosynthesis pathways of Z. bungeana and will be significant for the effective utilisation and ecological protection of Z. bungeana.

Background: Cichorium glandulosum Boiss. et Huet is used for treatment of liver disorders, and its effects are attributed to sesquiterpenes. This study aims to investigate the hepatoprotective effects of a sesquiterpene-rich fraction (SRF) from the aerial part of C. glandulosum on carbon tetrachloride (CCl₄)-induced acute hepatotoxicity in mice, and on priming with Bacillus Calmette–Guerin (BCG) followed by lipopolysaccharide (LPS)-induced immunological liver injury in mice. Methods: SRF was suspended in water and administered to mice at 0.05, 0.10 and 0.20 g/kg body weight for 7 consecutive days. An active control drug (bifendate pills) was suspended in distilled water and administered to mice at 0.40 g/kg body weight for 7 consecutive days. Hepatotoxicity was induced by intraperitoneal injection of 0.1% CCl₄ (0.2 mL/mouse) at 13 h before the last drug administration, or by tail intravenous injection of BCG (0.2 mL/mouse) before the first drug administration and LPS (0.2 mL/mouse; 8 μg) at 15 h before the last drug administration. Blood samples and the livers were collected for evaluation of the biochemical parameters of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin (TBIL). Results: SRF significantly reduced the impact of CCl₄ toxicity. The highest dose of SRF (0.20 g/kg) was the most effective, reflected by significant reductions in the levels of AST (P = 0.001), ALT (P = 0.000) and TBIL (P = 0.009). The serum enzymatic levels induced by BCG and subsequent LPS injection were significantly and dose-dependently restored by SRF, reflected by significant reductions in the levels of AST (P = 0.003), ALT (P = 0.003) and TBIL (P = 0.007) for the highest dose of SRF (0.20 g/kg). Conclusion: SRF is hepatoprotective in animal models of chemical and immunological acute liver injury.

To investigate effects of Ziziphora clinopodioides Lam. flavonoids on ischemia‐reperfusion injury of myocardial cells. After application of 6.25, 25, and 100 μg/mL Ziziphora clinopodioides Lam. flavonoids to H9C2 myocardial cells for 24H, they were treated for 4 hours with hydrogen peroxide to induce oxidative damage, whereas controls were cells without treatment and cells only incubated with hydrogen peroxide. Cell viability, lactate dehydrogenase release and mitochondrial membrane potential, intracellular Na+/K+‐ATPase activity and ATP content, and reactive oxygen species formation were monitored. An ischemia‐reperfusion injury rat model was established by left anterior descending coronary artery ligature in 48 Sprague‐Dawley rats, which were divided into positive control with isosorbide mononitrate (10 mg/kg) injection (n=8), model (ischemia‐reperfusion, n=8), sham‐operated (n=8), and Ziziphora clinopodioides Lam. flavonoids low (75 mg/kg, n=8), medium (150 mg/kg, n=8), and high concentration (300 mg/kg, n=8) groups. Superoxide dismutase activity and malondialdehyde content in homogenized hearts were measured and ischemic and infarction areas were triphenyl tetrazolium chloride and H&E stained for pathological and morphological examinations. Ziziphora clinopodioides Lam. flavonoids preconditioning improved cell viability (P<0.01), intracellular Na/K ATPase activity (P<0.001), and intracellular ATP content (P<0.001) and maintained mitochondrial membrane potential (P<0.05) in hydrogen peroxide treated H9C2 cells as well as rescued superoxide dismutase activity (P<0.01), decreased the malondialdehyde content (P<0.001), and reduced myocardial damage in the ischemia‐reperfusion rat model (P<0.001) compared to the controls. Ziziphora clinopodioides Lam. flavonoids may be an effective drug for protecting myocardial tissue from ischemia‐reperfusion injury by reducing reactive oxygen species related damage.

Ziziphora clinopodioides Lam. (Z. clinopodioides) is a traditional Chinese and ethnic medicine in Xinjiang, China with various therapeutic effects. It is primarily used for conditions such as heart disease, fever with chills, palpitations, and insomnia. Flavonoids are the main medicinal components of Z. clinopodioides, Interestingly, current research has increasingly focused on its neuroprotective effects. This study provides a comprehensive overview of the potential therapeutic applications of Z. clinopodioides and its constituents in central nervous system disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and cerebral ischemia-reperfusion injury. At present, about 25 flavonoids have been isolated and identified from various organs of Z. clinopodioides, including linarin, acacetin, hyperoside, quercetin, apigenin, luteolin, chrysin, kaempferol, baicalein, rutin and others. Modern pharmacological studies have revealed that Z. clinopodioides and its constituents exhibits neuroprotective effects in vitro and in vivo, and the mechanism of action is related to anti-apoptosis, anti-inflammatory, antioxidant, autophagy, endoplasmic reticulum stress and so on. Currently, there is limited research on the extracts of Z. clinopodioides and their potential mechanisms of action in these neurological disorders. It is also important to prioritize research on biosynthetic pathways and chemical modification approaches to fully explore and improve the neuroprotective potential of Z. clinopodioides and its flavonoids and establish a strong foundation for its clinical applications.