Effects of a histamine H4 receptor antagonist on cisplatin-induced anorexia in mice

Liujunzi Decoction ameliorated cisplatin-induced anorexia by inhibiting the JAK-STAT signaling pathway and coordinating anorexigenic and orexigenic neuropeptides in rats

ETHNOPHARMACOLOGICAL RELEVANCE

As a traditional Chinese formula, Liujunzi Decoction (LJZD) originated from the Yi Xue Zheng Zhuan, and has a promising effect in treating chemotherapy-induced anorexia (CIA).

AIM OF THE STUDY

The present study aims to investigate whether LJZD acts on interleukin-6 (IL-6)/leptin mediated janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway that regulates hypothalamus anorexigenic and orexigenic peptides to ameliorate CIA, and also elucidates the potential mechanism by metabolomic analysis.

MATERIALS AND METHODS

Network pharmacology analyses were conducted to screen out potential targets and pathways. The CIA rat model was established via an intraperitoneal injection of cisplatin. The histological changes of gastric antrum, liver and ileum were observed by HE staining. The serum levels of leptin, ghrelin, IL-6 and growth differentiation factor 15 (GDF15) were measured by ELISA. The JAK1/2 and STAT levels in gastric antrum and hypothalamus were detected by Western blot. The transcriptions of gastric antrum and hypothalamus IL-6R mRNA, and hypothalamus cocaine- and amphetamine-regulated transcript (CART), pro-opiomelanocortin (POMC), thyrotropin-releasing hormone (TRH), upregulated orexigenic peptides neuropeptide Y (NPY), and agouti-related protein (AGRP) mRNA were assessed by RT-qPCR. The blood samples of control, model and high dose LJZD groups were analyzed by metabolomic.

RESULTS

Network pharmacology highlighted the IL-6/leptin mediated JAK-STAT signaling pathway, which regulated downstream anorexigenic and orexigenic peptides in hypothalamus. LJZD ameliorated CIA via stimulating food intake and water consumption in rats. Cisplatin-induced gastric antrum, liver, ileum injuries were ameliorated, serum leptin level reduction was elevated, and ghrelin, IL-6, GDF15 level increases were decreased after LJZD treatments. In gastric antrum and hypothalamus, LJZD inhibited cisplatin-induced activation of JAK-STAT signaling pathway, downregulated the transcriptions of downstream anorexigenic peptides CART, POMC, TRH, and upregulated orexigenic peptides NPY, AGRP in hypothalamus. Importantly, the effect of LJZD in treating CIA might partly relate to the improvements of 23 abnormal metabolites.

CONCLUSION

This study implies that inhibiting JAK-STAT signaling pathway, regulating the expressions of anorexigenic and orexigenic peptides, and mediating various metabolic pathways might be potential mechanisms of LJZD's effect against CIA.

Thymoquinone and pentoxifylline enhance the chemotherapeutic effect of cisplatin by targeting Notch signaling pathway in mice

AIMS

Notch signaling is highly implicated in several cancers and chemoresistance. Therefore, Notch-targeted therapies might be beneficial in enhancing chemotherapeutic effect and cancer regression. This study aimed to investigate implication of Notch in development and progression of solid Ehrlich carcinoma (SEC) and enhancement of anticancer effect of cisplatin (CIS) by addition of thymoquinone (TQ) and pentoxifylline (PTX) through modulation of Notch.

MAIN METHODS

SEC was induced in mice as model for mammary carcinoma by s.c. injection of 1 × 10⁶ Ehrlich cells into back of the mice. On 12^th day, solid tumor was developed and mice were divided into seven groups; tumor control, early CIS (ECIS), ECIS + ETQ, ECIS + ETQ + EPTX, late CIS (LCIS), LCIS + LTQ, and LCIS + LTQ + LPTX. Early treatment was started on 12^th day, whereas late treatment was begun on 19^th day from tumor inoculation. At the endpoint, samples were collected for detection of Notch1, Hes1, Jagged1, β-catenin, TNF-α, IL-6, IFN-γ, IL-2, VEGF, apoptosis, CD4, and CD8.

KEY FINDINGS

Adding PTX and TQ to CIS significantly reduced Notch1, Hes1, Jagged1, β-catenin, TNF-α, IL-6, IFN-γ, and VEGF with increment in IL-2, CD4, CD8, and apoptotic cells. Moreover, early treated groups showed remarkable attenuation in tumor growth and the relevant parameters compared to their counterpart later groups.

SIGNIFICANCE

Addition of PTX with TQ to CIS showed a synergistic chemotherapeutic action and induced better oncostatic effect mainly through Notch suppression. Consequently, shutting Notch could be of great interest in promoting chemosensetivity and cancer control.

Activation of orexinergic and histaminergic pathway involved in therapeutic effect of histamine H4 receptor antagonist against cisplatin-induced anorexia in mice

We previously reported that hypothalamic tumor necrosis factor-alpha (TNF-α) mRNA expression via histamine H₄ receptors contributes to the development of cisplatin-induced anorexia; however, its precise mechanisms remain unclear. It has been reported that chemotherapeutic agents induce the suppression of orexin neuron activity, and the administration of orexin inhibits chemotherapeutic agent-induced gastric discomfort. Other studies demonstrated that the central administration of TNF-α impairs the orexinergic system, and that orexin excites the histaminergic system. We investigated the involvement of orexinergic and histaminergic systems in the therapeutic effect of an H₄ receptor antagonist against cisplatin-induced anorexia. Cisplatin decreased the expression of prepro-orexin mRNA, which encodes precursors of orexin, in the hypothalamus of mice. The period of expression decreased in parallel with the onset of anorexia, and treatment with an H₄ receptor antagonist (JNJ7777120, 10 mg/kg) inhibited the decrease in expression. The effect of the H₄ receptor antagonist on cisplatin-induced anorexia in mice was antagonized by an orexin OX₂ receptor antagonist (JNJ10397049, 5 mg/kg) rather than an orexin OX₁ receptor antagonist (SB408124, 30 mg/kg). Although an OX₂ receptor agonist (YNT-185, 20 mg/kg) or a histamine H₃ receptor inverse agonist (ciproxifan, 1 mg/kg) inhibited the cisplatin-induced anorexia, the inhibitory effect of the OX₂ receptor agonist was antagonized by an H₃ receptor silent antagonist (VUF5681, 5 mg/kg). The combination of JNJ7777120 (10 mg/kg) and ciproxifan (0.5 mg/kg) completely resolved the cisplatin-induced anorexia. These results suggest that activation of the orexinergic and histaminergic pathway is involved in the therapeutic effect of an H₄ receptor antagonist against cisplatin-induced anorexia.