Objective To examine the neuroanatomical substrates underlying the effects of minocycline in alleviating lipopolysaccharide(LPS)-induced neuroinflammation.Methods Forty C57BL/6 male mice were randomly and equally divi...Objective To examine the neuroanatomical substrates underlying the effects of minocycline in alleviating lipopolysaccharide(LPS)-induced neuroinflammation.Methods Forty C57BL/6 male mice were randomly and equally divided into eight groups.Over three conse-cutive days,saline was administered to four groups of mice and minocycline to the other four groups.Immediately after the administration of saline or minocycline on the third day,two groups of mice were additionally injected with saline and the other two groups were injected with LPS.Six or 24 hours after the last injection,mice were sacrificed and the brains were removed.Immunohistochemical staining across the whole brain was performed to detect microglia activation via Iba1 and neuronal activation via c-Fos.Morphology of microglia and the number of c-Fo-positive neurons were analyzed by Image-Pro Premier 3D.One-way ANOVA and Fisher’s least-significant differences were employed for statistical analyses.Results Minocycline alleviated LPS-induced neuroinflammation as evidenced by reduced activation of microglia in multiple brain regions,including the shell part of the nucleus accumbens(Acbs),paraventricular nucleus(PVN)of the hypothalamus,central nucleus of the amygdala(CeA),locus coeruleus(LC),and nucleus tractus solitarius(NTS).Minocycline significantly increased the number of c-Fo-positive neurons in NTS and area postrema(AP)after LPS treatment.Furthermore,in NTS-associated brain areas,including LC,lateral parabrachial nucleus(LPB),periaqueductal gray(PAG),dorsal raphe nucleus(DR),amygdala,PVN,and bed nucleus of the stria terminali(BNST),minocycline also significantly increased the number of c-Fo-positive neurons after LPS administration.Conclusion Minocycline alleviates LPS-induced neuroinflammation in multiple brain regions,possibly due to increased activation of neurons in the NTS-associated network.展开更多
Objective:Oncocardiology is increasingly hot research field/topic in the clinical management of cancer with anti-angiogenic therapy of vascular endothelial growth factor(VEGF)that may cause cardiovascular toxicity,suc...Objective:Oncocardiology is increasingly hot research field/topic in the clinical management of cancer with anti-angiogenic therapy of vascular endothelial growth factor(VEGF)that may cause cardiovascular toxicity,such as hypertension via vascular dysfunction and attenuation of eNOS/NO signaling in the baroreflex afferent pathway.The aim of the current study was to evaluate the potential roles of VEGF/VEGF receptors(VEGFRs)expressed in the baroreflex afferent pathway in autonomic control of blood pressure(BP)regulation.Methods:The distribution and expression of VEGF/VEGFRs were detected in the nodose ganglia(NG)and nucleus of tractus solitary(NTS)using immunostaining and molecular approaches.The direct role of VEGF was tested by NG microinjection under physiological and hypertensive conditions.Results:Immunostaining data showed that either VEGF or VEGFR2/VEGFR3 was clearly detected in the NG and NTS of adult male rats.Microinjection of VEGF directly into the NG reduced the mean blood pressure(MBP)dose-dependently,which was less dramatic in renovascular hypertension(RVH)rats,suggesting the VEGF-mediated depressor response by direct activation of the 1st-order baroreceptor neurons in the NG under both normal and disease conditions.Notably,this reduced depressor response in RVH rats was directly caused by the downregulation of VEGFR2,which compensated the up regulation of VEGF/VEGFR3 in the NG during the development of hypertension.Conclusion:It demonstrated for the first time that the BP-lowering property of VEGF/VEGFRs signaling via the activation of baroreflex afferent function may be a common target/pathway leading to BP dysregulation in anti-angiogenic therapy.展开更多
Central sensitization is essential in maintaining chronic pain induced by chronic pancreatitis(CP),but cortical modulation of painful CP remains elusive.Here,we examined the role of the anterior cingulate cortex(ACC)i...Central sensitization is essential in maintaining chronic pain induced by chronic pancreatitis(CP),but cortical modulation of painful CP remains elusive.Here,we examined the role of the anterior cingulate cortex(ACC)in the pathogenesis of abdominal hyperalgesia in a rat model of CP induced by intraductal administration of trinitrobenzene sulfonic acid(TNBS).TNBS treatment resulted in long-term abdominal hyperalgesia and anxiety in rats.Morphological data indicated that painful CP induced a significant increase in FOS-expressing neurons in the nucleus tractus solitarii(NTS)and ACC,and some FOS-expressing neurons in the NTS projected to the ACC.In addition,a larger portion of ascending fibers from the NTS innervated pyramidal neurons,the neural subpopulation primarily expressing FOS under the condition of painful CP,rather than GABAergic neurons within the ACC.CP rats showed increased expression of vesicular glutamate transporter 1,and increased membrane trafficking and phosphorylation of the N-methyl-D-aspartate receptor(NMDAR)subunit NR2B and theα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor(AMPAR)subunit GluR1 within the ACC.Microinjection of NMDAR and AMPAR antagonists into the ACC to block excitatory synaptic transmission significantly attenuated abdominal hyperalgesia in CP rats,which was similar to the analgesic effect of endomorphins injected into the ACC.Specifically inhibiting the excitability of ACC pyramidal cells via chemogenetics reduced both hyperalgesia and comorbid anxiety,whereas activating these neurons via optogenetics failed to aggravate hyperalgesia and anxiety in CP rats.Taken together,these findings provide neurocircuit,biochemical,and behavioral evidence for involvement of the ACC in hyperalgesia and anxiety in CP rats,as well as novel insights into the cortical modulation of painful CP,and highlights the ACC as a potential target for neuromodulatory interventions in the treatment of painful CP.展开更多
基金supported by the research grants from the National Natural Science Foundation of China(81625008 and 31970952)the National Key Research and Development Program of China(2020YFA0804500,2020YFA0804502)。
文摘Objective To examine the neuroanatomical substrates underlying the effects of minocycline in alleviating lipopolysaccharide(LPS)-induced neuroinflammation.Methods Forty C57BL/6 male mice were randomly and equally divided into eight groups.Over three conse-cutive days,saline was administered to four groups of mice and minocycline to the other four groups.Immediately after the administration of saline or minocycline on the third day,two groups of mice were additionally injected with saline and the other two groups were injected with LPS.Six or 24 hours after the last injection,mice were sacrificed and the brains were removed.Immunohistochemical staining across the whole brain was performed to detect microglia activation via Iba1 and neuronal activation via c-Fos.Morphology of microglia and the number of c-Fo-positive neurons were analyzed by Image-Pro Premier 3D.One-way ANOVA and Fisher’s least-significant differences were employed for statistical analyses.Results Minocycline alleviated LPS-induced neuroinflammation as evidenced by reduced activation of microglia in multiple brain regions,including the shell part of the nucleus accumbens(Acbs),paraventricular nucleus(PVN)of the hypothalamus,central nucleus of the amygdala(CeA),locus coeruleus(LC),and nucleus tractus solitarius(NTS).Minocycline significantly increased the number of c-Fo-positive neurons in NTS and area postrema(AP)after LPS treatment.Furthermore,in NTS-associated brain areas,including LC,lateral parabrachial nucleus(LPB),periaqueductal gray(PAG),dorsal raphe nucleus(DR),amygdala,PVN,and bed nucleus of the stria terminali(BNST),minocycline also significantly increased the number of c-Fo-positive neurons after LPS administration.Conclusion Minocycline alleviates LPS-induced neuroinflammation in multiple brain regions,possibly due to increased activation of neurons in the NTS-associated network.
基金supported by the National Natural Science Foundation of China(31171122,81573431,81971326 for B.-y.,Li).
文摘Objective:Oncocardiology is increasingly hot research field/topic in the clinical management of cancer with anti-angiogenic therapy of vascular endothelial growth factor(VEGF)that may cause cardiovascular toxicity,such as hypertension via vascular dysfunction and attenuation of eNOS/NO signaling in the baroreflex afferent pathway.The aim of the current study was to evaluate the potential roles of VEGF/VEGF receptors(VEGFRs)expressed in the baroreflex afferent pathway in autonomic control of blood pressure(BP)regulation.Methods:The distribution and expression of VEGF/VEGFRs were detected in the nodose ganglia(NG)and nucleus of tractus solitary(NTS)using immunostaining and molecular approaches.The direct role of VEGF was tested by NG microinjection under physiological and hypertensive conditions.Results:Immunostaining data showed that either VEGF or VEGFR2/VEGFR3 was clearly detected in the NG and NTS of adult male rats.Microinjection of VEGF directly into the NG reduced the mean blood pressure(MBP)dose-dependently,which was less dramatic in renovascular hypertension(RVH)rats,suggesting the VEGF-mediated depressor response by direct activation of the 1st-order baroreceptor neurons in the NG under both normal and disease conditions.Notably,this reduced depressor response in RVH rats was directly caused by the downregulation of VEGFR2,which compensated the up regulation of VEGF/VEGFR3 in the NG during the development of hypertension.Conclusion:It demonstrated for the first time that the BP-lowering property of VEGF/VEGFRs signaling via the activation of baroreflex afferent function may be a common target/pathway leading to BP dysregulation in anti-angiogenic therapy.
基金supported by the National Natural Science Foundations of China(81620108008 and 31971112)the Innovation Capability Support Program of Shaanxi Province,China(2021TD-57).
文摘Central sensitization is essential in maintaining chronic pain induced by chronic pancreatitis(CP),but cortical modulation of painful CP remains elusive.Here,we examined the role of the anterior cingulate cortex(ACC)in the pathogenesis of abdominal hyperalgesia in a rat model of CP induced by intraductal administration of trinitrobenzene sulfonic acid(TNBS).TNBS treatment resulted in long-term abdominal hyperalgesia and anxiety in rats.Morphological data indicated that painful CP induced a significant increase in FOS-expressing neurons in the nucleus tractus solitarii(NTS)and ACC,and some FOS-expressing neurons in the NTS projected to the ACC.In addition,a larger portion of ascending fibers from the NTS innervated pyramidal neurons,the neural subpopulation primarily expressing FOS under the condition of painful CP,rather than GABAergic neurons within the ACC.CP rats showed increased expression of vesicular glutamate transporter 1,and increased membrane trafficking and phosphorylation of the N-methyl-D-aspartate receptor(NMDAR)subunit NR2B and theα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor(AMPAR)subunit GluR1 within the ACC.Microinjection of NMDAR and AMPAR antagonists into the ACC to block excitatory synaptic transmission significantly attenuated abdominal hyperalgesia in CP rats,which was similar to the analgesic effect of endomorphins injected into the ACC.Specifically inhibiting the excitability of ACC pyramidal cells via chemogenetics reduced both hyperalgesia and comorbid anxiety,whereas activating these neurons via optogenetics failed to aggravate hyperalgesia and anxiety in CP rats.Taken together,these findings provide neurocircuit,biochemical,and behavioral evidence for involvement of the ACC in hyperalgesia and anxiety in CP rats,as well as novel insights into the cortical modulation of painful CP,and highlights the ACC as a potential target for neuromodulatory interventions in the treatment of painful CP.
