Background: Isoliquiritigenin, a key pharmacologically active compound derived from the traditional Chinese medicine Glycyrrhizae Radix et Rhizoma, can be further modified into various high-value 5-deoxyflavones, demonstrating significant potential for pharmaceutical development. Currently, the supply of isoliquiritigenin primarily depends on plant extraction. However, heterologous synthesis using microbial cell factories presents a promising alternative, offering a solution to resource limitations caused by the dwindling availability of Glycyrrhiza uralensis. Objective: This study aimed to employ heterologous synthesis in yeast strains for the stable and high-efficiency production of isoliquiritigenin. Methods: First, a stable chassis strain for isoliquiritigenin production was constructed by integrating optimized biosynthetic pathway enzyme genes. A type IV noncatalytic chalcone isomerase-like protein and a synthetic protein scaffold system were employed to enhance the metabolic channeling of key pathway enzymes. Subsequently, yeast metabolism was fine-tuned to balance precursor supply, and cofactor engineering strategies were implemented to increase nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) availability, thereby ensuring the catalytic efficiency of the key enzyme chalcone reductase. Results: The engineered strain Y21-2 achieved a 24.4-fold increase in isoliquiritigenin titer compared to the original strain. Additionally, the proportion of the by-product naringenin chalcone was reduced by 67.8%, marking the first instance in which the ratio of C-5 hydroxylated by-products was minimized to 10.4% during the microbial synthesis of 5-deoxyflavones. Conclusion: This work provides a valuable reference for the efficient and sustainable production of isoliquiritigenin, laying a solid foundation for further pathway optimization and the biotechnological synthesis of other high-value natural 5-deoxyflavones.

OBJECTIVE To compare the short-term efficacy of autologous frozen tragus perichondrium and fresh perichondrium in repairing tympanic membrane perforations,and to explore the clinical application value of autologous frozen tragus perichondrium.METHODS Twenty-five patients with bilateral tympanic membrane perforations from March 2021 to October 2023 were selected,including 7 males and 18 females.Bilateral tympanoplasty was completed in stages.The initial operation was set as the control group,in which the ventral perichondrium of the tragus was used for tympanoplasty,and the dorsal perichondrium of the tragus was reserved and stored at-80℃ultra-low temperature in a sterile container.The second operation was set as the observation group,in which the thawed frozen perichondrium was used for contralateral tympanoplasty.The differences in the healing rate of tympanic membrane,postoperative hearing,operation time and surgical bleeding volume were compared between the two groups.RESULTS All patients were followed up for three months.The success rate of tympanic membrane healing in the observation group was 96%(24/25),and that in the control group was 92%(23/25).There was no statistically significant difference between the two groups(χ2=0.36,P>0.05).The operation time and surgical bleeding volume of patients in the observation group were lower than those in the control group[(48.64±4.64)min vs.(67.92±5.69)min,(5.32±1.54)ml vs.(9.65±1.73)ml],and the differences were statistically significant(t=13.93,t=12.09,P all<0.05).The postoperative air conduction hearing thresholds and air-bone conduction gap of the two groups of patients were lower than those before operation(all P<0.05).There was no difference in air conduction hearing threshold,bone conduction hearing threshold and air-bone conduction difference between the groups(all P>0.05).CONCLUSION The application of autologous frozen tragus perichondrium has effectively shortened the operation time of the contralateral ear,avoided the trauma caused by taking materials again,and has the characteristics of minimally invasive and high efficiency.The method is feasible and the curative effect is accurate.

The pathophysiology of visceral pain in patients with irritable bowel syndrome remains largely unknown. Our previous study showed that neonatal maternal deprivation (NMD) does not induce visceral hypersensitivity at the age of 6 weeks in rats. The aim of this study was to determine whether NMD followed by adult stress at the age of 6 weeks induces visceral pain in rats and to investigate the roles of adrenergic signaling in visceral pain. Here we showed that NMD rats exhibited visceral hypersensitivity 6 h and 24 h after the termination of adult multiple stressors (AMSs). The plasma level of norepinephrine was significantly increased in NMD rats after AMSs. Whole-cell patch-clamp recording showed that the excitability of dorsal root ganglion (DRG) neurons from NMD rats with AMSs was remarkably increased. The expression of β adrenergic receptors at the protein and mRNA levels was markedly higher in NMD rats with AMSs than in rats with NMD alone. Inhibition of β adrenergic receptors with propranolol or butoxamine enhanced the colorectal distention threshold and application of butoxamine also reversed the enhanced hypersensitivity of DRG neurons. Overall, our data demonstrate that AMS induces visceral hypersensitivity in NMD rats, in part due to enhanced NE-β adrenergic signaling in DRGs.
Adrenergic Agents ; pharmacology ; Animals ; Ganglia, Spinal ; drug effects ; Hyperalgesia ; drug therapy ; physiopathology ; Hypersensitivity ; drug therapy ; Male ; Maternal Deprivation ; Neurons ; drug effects ; Patch-Clamp Techniques ; methods ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Stress, Physiological ; physiology ; Visceral Pain ; chemically induced ; metabolism

Chronic visceral hypersensitivity is an important type of chronic pain with unknown etiology and pathophysiology. Recent studies have shown that epigenetic regulation plays an important role in the development of chronic pain conditions. However, the role of miRNA-325-5p in chronic visceral pain remains unknown. The present study was designed to determine the roles and mechanism of miRNA-325-5p in a rat model of chronic visceral pain. This model was induced by neonatal colonic inflammation (NCI). In adulthood, NCI led to a significant reduction in the expression of miRNA-325-5p in colon-related dorsal root ganglia (DRGs), starting to decrease at the age of 4 weeks and being maintained to 8 weeks. Intrathecal administration of miRNA-325-5p agomir significantly enhanced the colorectal distention (CRD) threshold in a time-dependent manner. NCI also markedly increased the expression of CCL2 (C-C motif chemokine ligand 2) in colon-related DRGs at the mRNA and protein levels relative to age-matched control rats. The expression of CXCL12, IL33, SFRS7, and LGI1 was not significantly altered in NCI rats. CCL2 was co-expressed in NeuN-positive DRG neurons but not in glutamine synthetase-positive glial cells. Furthermore, CCL2 was mainly expressed in isolectin B4-binding- and calcitonin gene-related peptide-positive DRG neurons but in few NF-200-positive cells. More importantly, CCL2 was expressed in miR-325-5p-positive DRG neurons. Intrathecal injection of miRNA-325-5p agomir remarkably reduced the upregulation of CCL2 in NCI rats. Administration of Bindarit, an inhibitor of CCL2, markedly raised the CRD threshold in NCI rats in a dose- and time-dependent manner. These data suggest that NCI suppresses miRNA-325-5p expression and enhances CCL2 expression, thus contributing to visceral hypersensitivity in adult rats.

BACKGROUND/AIMS: This study was to investigate whether transforming growth factor-β1 (TGF-β1) plays a role in hyperalgesia in chronic pancreatitis (CP) and the underlying mechanisms. METHODS: CP was induced in male adult rats by intraductal injection of trinitrobenzene sulfonic acid (TNBS). Abdominal hyperalgesia was assessed by referred somatic behaviors to mechanical stimulation of rat abdomen. Dil dye injected into the pancreas was used to label pancreas-specific dorsal root ganglion (DRG) neurons. Whole cell patch clamp recordings and calcium imaging were performed to examine the effect of TGF-β1 on acutely isolated pancreas-specific DRG neurons. Western blot analysis was carried out to measure the expression of TGF-β1 and its receptors. RESULTS: TNBS injection significantly upregulated expression of TGF-β1 in the pancreas and DRGs, and TGF-β1 receptors in DRGs (T9-T13) in CP rats. Intrathecal injection of TGF-β receptor I antagonist SB431542 attenuated abdominal hyperalgesia in CP rats. TGF-β1 application depolarized the membrane potential and caused firing activity of DRG neurons. TGF-β1 application also reduced rheobase, hyperpolarized action potential threshold, and increased numbers of action potentials evoked by current injection of pancreas-specific DRG neurons. TGF-β1 application also increased the concentration of intracellular calcium of DRG neurons, which was inhibited by SB431542. Furthermore, intrathecal injection of TGF-β1 produced abdominal hyperalgesia in healthy rats. CONCLUSIONS: These results suggest that TGF-β1 enhances neuronal excitability and increases the concentration of intracellular calcium. TGF-β1 and its receptors are involved in abdominal hyperalgesia in CP. This and future study might identify a potentially novel target for the treatment of abdominal pain in CP.
Abdomen ; Abdominal Pain ; Action Potentials ; Adult ; Animals ; Blotting, Western ; Calcium ; Diagnosis-Related Groups ; Fires ; Ganglia, Spinal ; Humans ; Hyperalgesia ; Injections, Spinal ; Male ; Membrane Potentials ; Neurons* ; Pancreas ; Pancreatitis, Chronic* ; Rats*

BACKGROUND/AIMS: Patients with long-standing diabetes often demonstrate intestinal dysfunction and abdominal pain. However, the pathophysiology of abdominal pain in diabetic patients remains elusive. The purpose of study was to determine roles of voltage-gated sodium channels in dorsal root ganglion (DRG) in colonic hypersensitivity of rats with diabetes. METHODS: Diabetic models were induced by a single intraperitoneal injection of streptozotocin (STZ; 65 mg/kg) in adult female rats, while the control rats received citrate buffer only. Behavioral responses to colorectal distention were used to determine colonic sensitivity in rats. Colon projection DRG neurons labeled with DiI were acutely dissociated for measuring excitability and sodium channel currents by whole-cell patch clamp recordings. Western blot analysis was employed to measure the expression of NaV1.7 and NaV1.8 of colon DRGs. RESULTS: STZ injection produced a significantly lower distention threshold than control rats in responding to colorectal distention. STZ injection also depolarized the resting membrane potentials, hyperpolarized action potential threshold, decreased rheobase and increased frequency of action potentials evoked by 2 and 3 times rheobase and ramp current stimulation. Furthermore, STZ injection enhanced neuronal sodium current densities of DRG neurons innervating the colon. STZ injection also led to a significant upregulation of NaV1.7 and NaV1.8 expression in colon DRGs compared with age and sex-matched control rats. CONCLUSIONS: Our results suggest that enhanced neuronal excitability following STZ injection, which may be mediated by upregulation of NaV1.7 and NaV1.8 expression in DRGs, may play an important role in colonic hypersensitivity in rats with diabetes.
Abdominal Pain ; Action Potentials ; Adult ; Animals ; Architectural Accessibility ; Blotting, Western ; Citric Acid ; Colon* ; Diagnosis-Related Groups ; Female ; Ganglia, Spinal ; Humans ; Hypersensitivity* ; Injections, Intraperitoneal ; Membrane Potentials ; Neurons ; Rats* ; Sensory Receptor Cells* ; Sodium ; Sodium Channels ; Streptozocin ; Up-Regulation ; Voltage-Gated Sodium Channels*

Objective:In oder to investigate the effect of Chuanmingshen violaceum polysaccharides ( CVP) and Solfated Chua-nmingshen violaceum polysaccharides ( SCVP) on immunosuppression induced by cyclophosphamide ( CY) in mice.Methods: CY were used to induce immunosuppression in mice;Spleen and thymus indexes were used to evaluate the immune organs indexes;the [3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltet-razolium bromide,MTT] method was used to detect the proliferation of spleen lymphocytes of each group;the concentrations of IFN-γand IL-2 were assayed by ELISA kit.Results: SCVP and CVP could resist immunosuppression by promoting lymphocyte proliferation, increasing the contents of IFN-γ and IL-2, promoting immune organs development in immunosuppressive mice induced by CY.Conclusion:SCVP and CVP exhibited the potential to used as immunopotentiator.

The UL49.5 gene of most herpesviruses is conserved and encodes glycoprotein N. However, the UL49.5 protein of duck enteritis virus (DEV) (pUL49.5) has not been reported. In the current study, the DEV pUL49.5 gene was first subjected to molecular characterization. To verify the predicted intracellular localization of gene expression, the recombinant plasmid pEGFP-C1/pUL49.5 was constructed and used to transfect duck embryo fibroblasts. Next, the recombinant plasmid pDsRed1-N1/glycoprotein M (gM) was produced and used for co-transfection with the pEGFP-C1/pUL49.5 plasmid to determine whether DEV pUL49.5 and gM (a conserved protein in herpesviruses) colocalize. DEV pUL49.5 was thought to be an envelope glycoprotein with a signal peptide and two transmembrane domains. This protein was also predicted to localize in the cytoplasm and endoplasmic reticulum with a probability of 66.7%. Images taken by a fluorescence microscope at different time points revealed that the DEV pUL49.5 and gM proteins were both expressed in the cytoplasm. Overlap of the two different fluorescence signals appeared 12 h after transfection and continued to persist until the end of the experiment. These data indicate a possible interaction between DEV pUL49.5 and gM.
Animals ; Ducks/virology ; Genes, Viral/genetics ; Mardivirus/*genetics ; Membrane Glycoproteins/*genetics ; Microscopy, Fluorescence ; Phylogeny ; Polymerase Chain Reaction/veterinary ; Viral Envelope Proteins/*genetics

OBJECTIVE: To explore curative effect with pedicle flap of nasal septum-basis nasi and temporal muscucofascial flap to repair nasal septal perforation. METHOD: Dissecting mucoperichondrium and mucoperioseptum around the perforation and taking dowm and out xia-ward to the floor of nasal cavity to make a inferior extremity pedicle flap. Then,the flap was tumbled and sutured onto raw surface of contralateral side through perforation. Reapplicating autoallergic temporal musculofascial flap to repair another side perforation. RESULT: Repairing perforation Sin twelve cases were sucessfully healed in endoscope. CONCLUSION The pedicle flap of nasal septum-basis nasi and temporal muscucofascial flap is easy to acquire and no rejection. The flap has good blood supplying, high survival rate and provides adequate transplantating materail to repair comparatively large perforation.
Endoscopes ; Humans ; Nasal Cavity ; Nasal Septal Perforation ; Nasal Septum ; pathology ; surgery ; Paranasal Sinuses ; Surgical Flaps ; Wound Healing

Aim To investigate the role of locus coeruleus(LC)-norepinephrinergic system and sympathetic nervous system in immunosuppression under cold stress, using 6-hydroxydopamine(6-OHDA) as chemical sympathectomy.Methods Rats were maintained in cold chamber at 4℃ for 4 h.The 51Cr release assay from YAC-1 cells was used to determine the splenic NK cell activity, the double staining of ABC method was employed to observe the immunoreactive expression of Fos, arginine-vasopressin(AVP), oxytocin(OT) and tyrosine hydroxylase(TH), and conventional radioimmunoassay was used to measure plasma corticosterone (CORT) concentrations.Results Central sympathectomy with intracerebroventricular(i.c.v.) injection of 6-OHDA r educed significantly the elevation of plasma corticosterone level, the expressio n of Fos in hypothalamic paraventricular nucleus(PVN) and in locus coeruleus(LC ), as well as the suppression of NK activity induced by cold stress at 4℃ for 4 h. Peripheral sympathectomy with intraperitoneal (i.p.) injection of 6-OHDA al so reversed the cold stress-induced suppression of NK cytotoxicity, but without significant effect on Fos expression in brain. Double staining showed that amon g the Fos-positive neurons in PVN only a few co-expressed Fos and AVP or Fos a nd OT, while in LC the majority of Fos-positive neurons co-expressed Fos and T H.Conclusion The mechanism of suppression of NK activity induce d by cold stress may be mediated through HPA axis activated partially by central LC-norepinephrinergic system and through the peripheral sympathetic nervous system.