Simultaneous Analysis for Quality Control of Traditional Herbal Medicine, Gungha-Tang, Using Liquid Chromatography–Tandem Mass Spectrometry

Gungha-tang (GHT), a traditional herbal medicine, consists of nine medicinal herbs (Cnidii Rhizoma, Pinelliae Tuber, Poria Sclerotium, Citri Unshius Pericarpium, Citri Unshius Pericarpium Immaturus, Aurantii Fructus Immaturus, Atracylodis Rhizoma Alba, Glycyrrhizae Radix et Rhizoma, and Zingiberis Rhizoma Recens). It has been used for various diseases caused by phlegm. This study aimed to develop and verify the simultaneous liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis method, using nine marker components (liquiritin apioside, neoeriocitrin, narirutin, naringin, hesperidin, neohesperidin, liquiritigenin, glycyrrhizin, and 6-shogaol) for quality control of GHT. LC–MS/MS analysis was conducted using a Waters TQ-XS system. All marker analytes were separated on a Waters Acquity UPLC BEH C₁₈ column (2.1 × 100 mm, 1.7 μm) using gradient elution with a distilled water solution (containing 5 mM ammonium formate and 0.1% [v/v] formic acid)–acetonitrile mobile phase. LC–MS/MS multiple reaction monitoring (MRM) analysis was carried out in negative and positive ion modes of an electrospray ionization source. The developed LC–MS/MS MRM method was validated by examining the linearity, limits of detection and quantification, recovery, and precision. LOD and LOQ values of nine markers were calculated as 0.02–8.33 ng/mL and 0.05–25.00 ng/mL. The recovery was determined to be 89.00–118.08% and precision was assessed with a coefficient of variation value of 1.74–8.64%. In the established LC–MS/MS MRM method, all markers in GHT samples were detected at 0.003–16.157 mg/g. Information gathered during the development and verification of the LC–MS/MS method will be useful for the quality assessment of GHT and other herbal medicines.

Antidepressant-like effects of Xiaochaihutang in perimenopausal mice

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaochaihutang (XCHT) is a traditional Chinese medicine prescription for thousand years in China. Our previous researches show that XCHT has antidepressant-like effects in several depression models, but effect and mechanism of XCHT in perimenopausal depression are still vague.

AIM OF THE STUDY

To reveal the antidepressant-like effect and mechanism of XCHT in perimenopausal mice.

MATERIALS AND METHODS

Perimenopausal depression model is executed by ovariectomy combined with chronic unpredictable mild stress (OVX-CUMS). Tail suspension test (TST), forced swim test (FST), elevated plus-maze (EPM), novelty suppressed feeding (NSF) and locomotor activity are used to assess antidepressant-like effects of XCHT. The Level of estradiol (E₂), follicle-stimulating hormone (FSH), gonadotrophin releasing hormone (GnRH), corticosterone (CORT), adrenocorticotrophic hormone (ACTH) and corticotropin releasing hormone (CRH) are evaluated by ELISA. Antidepressant mechanisms of XCHT in OVX-CUMS mice are analyzed by 5-hydroxytryptamine (5-HT), tryptophan hydroxylase 2 (TPH2) and estrogen receptor α and β (ERα/β).

RESULTS

The results show that OVX-CUMS significantly increases the immobility time in TST and FST, increases latency to feed, decreases food consumption in NSF and both the time spend and number of entries in open arms in EPM. While, oral administration of XCHT can significantly normalize above depression-like behaviors in OVX-CUMS mice. Moreover, XCHT also remarkably normalized levels of 5-HT, 5-HIAA, E₂, GnRH, CORT, ACTH and CRH in OVX-CUMS mice. Finally, the expression of ERβ and TPH2 are decreased by OVX-CUMS in prefrontal cortex and hypothalamus, and XCHT can restore these decrease.

CONCLUSION

Current findings suggest XCHT can alleviate perimenopausal depression-like behaviors, restore 5-HT and hormones in OVX-CUMS mice, which may be related to normalizing the functions of HPA/HPO axis and enhancing expression of ERβ and TPH2 in prefrontal cortex and hypothalamus.

Quantitative proteomics reveal antidepressant potential protein targets of xiaochaihutang in corticosterone induced model of depression

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaochaihutang (XCHT), one of famous Chinese herbal prescription for treating Shaoyang symptom, has been used successfully in depressive disorders for many years. Our laboratory has demonstrated that XCHT remarkably alleviated various depressive behaviors induced by several depressive animal models, but previous studies only focused on one or several protein targets, lacked dynamic change and interrelation of proteins. Therefore, potential protein targets and mechanisms are required further systematic investigation.

AIM OF THE STUDY

To discover and assess the differentially expressed proteins (DEPs) of hippocampus after oral administration of XCHT in corticosterone (CORT) induced model of depression by using isobaric tags for relative and absolute quantification (iTRAQ) analysis.

MATERIALS AND METHODS

The antidepressant effects of XCHT were assessed by two behavioral despair models (forced swimming test and tail suspension test) in CORT induced model of depression. The DEPs of hippocampus after XCHT treatment were investigated by iTRAQ analysis. Potential protein targets and mechanisms were assessed by gene ontology (GO), Kyoto encyclopedia of gene and genomes (KEGG) and protein-protein interaction (PPI) network.

RESULTS

Our data demonstrated XCHT could significantly improve depressive behaviors. A total of 241 DEPs were identified after XCHT treatment, including 68 up regulation and 173 down regulation proteins. GO enrichment results indicated that XCHT mainly regulated intracellular structural proteins involved in cellular response to stress, transferase activity and steroid hormone. KEGG enrichment analysis showed that endocytosis might be the principal pathway of XCHT on depression. PPI analysis predicted cell division cycle and apoptosis regulator protein 1 (Ccar1) and Calretinin (Calb2) might play the central roles in XCHT's antidepressant network.

CONCLUSION

Our results indicate that XCHT plays the important roles in antidepressant action by restoring DEPs, which results in the dysregulation of hippocampal neurogenesis, neurotransmitter and steroid hormone. The current results wish to provide novel perspectives for revealing the potential protein targets of XCHT on depression.

Antidepressant-like effects of Xiaochaihutang in a neuroendocrine mouse model of anxiety/depression

ETHNOPHARMACOLOGICAL RELEVANCE

Hyperactivity of hypothalamic-pituitary-adrenal (HPA) axis is often observed in the pathophysiology of depression. Antidepressant therapy can restore hippocampal neurogenesis to rescue the HPA axis regulation defects. Xiaochaihutang (XCHT), a famous Chinese herbal formula, has been used clinically in depressive disorders in China. Our previous studies have demonstrated XCHT improved depressive-like behaviors in chronic unpredictable mild stress rat, but the underlying mechanisms of XCHT on hippocampal neurogenesis and the HPA axis were still unclear.

MATERIALS AND METHODS

We used chronic corticosterone (CORT)-induced mouse model of anxiety/depression to investigate antidepressant-like effects of XCHT by several physical and behavioral testing, including body weight, coat state, open field test, elevated plus maze, tail suspension test and forced swimming test. The integrity of negative feedback function on HPA axis was assessed by the dexamethasone (DEX) suppression test. In addition, Ki-67 and doublecortin (DCX) were performed to assess hippocampal cell proliferation and neurogenesis by immunohistochemistry. Chemical profile of active constituents in brain after oral administration of XCHT was revealed by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

RESULTS

Our results showed that oral administration of XCHT (2.3, 7 and 21g/kg) for 30 days remarkably normalized chronic CORT-induced the slowness in weight gain, the deterioration in coat state, the escape behavior in open field test and elevated plus maze, and the increase of immobility time in tail suspension test and forced swimming test. Moreover, XCHT significantly reversed chronic CORT-induced the reduction of DEX-induced plasma corticosterone/c-Fos suppression and Ki-67/DCX positive cells. Finally, a total 13 potential active constituents in brain were identified by UPLC-MS/MS after oral administration of XCHT, including 10 prototype components and 3 metabolites.

CONCLUSIONS

Our findings showed that XCHT could remarkably alleviate chronic CORT-induced anxiety/depression-like behaviors, which were probably attribute to promoting hippocampal neurogenesis and remodeling the integrity of the negative feedback loop on HPA axis. The constituents identified in brain might contribute to understanding the therapeutic basis of XCHT on depression.

Neurological mechanism of Xiaochaihutang's antidepressant-like effects to socially isolated adult rats

Objectives

Xiaochaihutang (XCHT) has antidepressant effects in multiple animal models of depression in our previous studies. But the antidepressant effects and exact mechanisms of XCHT in a rat model of chronic social isolation stress (CSIS) have never been studied. We therefore aimed to investigate the effects of XCHT on depressive/anxiety-related behaviours of CSIS-exposed rats and understand the neurological mechanism involving neurogenesis.

Methods

We established the CSIS model and then investigated the effects of XCHT on behavioural change. HPLC-MS/MS was adopted to quantify neurotransmitter levels in the cerebrospinal fluid (CSF). Immunofluorescence technology was used to study the effects of XCHT on neurogenesis; while expressions of 5-HT1A receptor signalling pathway in the hippocampus were measured using Western blotting.

Key Findings

Xiaochaihutang significantly alleviated depressive/anxiety-like behaviours of CSIS-exposed rats. XCHT significantly regulated levels of monoamine neurotransmitters in the CSF without affecting Glu, GABA and ACh. XCHT also significantly increased neurogenesis in CSIS-exposed rats. Additionally, XCHT reversed CSIS-induced decrease of 5-HT1A receptor expression and promoted the expression of BDNF in the hippocampus.

Conclusion

Our results suggest that XCHT could significantly regulate the depressive/anxiety-like behaviours induced by CSIS, which are likely attributed to the promotion of hippocampal neurogenesis and neurotrophin expressions through the activation of serotonergic system.