Serum level of vascular endothelial growth factor decreased in chronic ketamine abusers

Molecular Pathophysiology and Potential Therapeutic Strategies of Ketamine-Related Cystitis

Ketamine was first synthesized as a clinical medicine for anesthesia in 1970. It has been used as a recreational drug because of its low cost and hallucination effect in the past decade. Part of ketamine abusers may experience ketamine-related cystitis (KC) and suffer from lower urinary tract symptoms, including urinary frequency, urgency, and severe bladder pain. As the disease progression, a contracted bladder, petechial hemorrhage of the bladder mucosa, and ureteral stricture with hydronephrosis may occur. The pathophysiology of KC is still uncertain, although several hypotheses have been raised. Cessation of ketamine abuse is critical for the management of KC to prevent progressive disease, and effective treatment has not been established. Research has provided some theoretical bases for developing in vitro experiments, animal models, and clinical trials. This review summarized evidence of molecular mechanisms of KC and potential treatment strategies for KC. Further basic and clinical studies will help us better understand the mechanism and develop an effective treatment for KC.

Low-Intensity Extracorporeal Shock Wave Therapy Promotes Bladder Regeneration and Improves Overactive Bladder Induced by Ovarian Hormone Deficiency from Rat Animal Model to Human Clinical Trial

Postmenopausal women with ovary hormone deficiency (OHD) are subject to overactive bladder (OAB) symptoms. The present study attempted to elucidate whether low-intensity extracorporeal shock wave therapy (LiESWT) alters bladder angiogenesis, decreases inflammatory response, and ameliorates bladder hyperactivity to influence bladder function in OHD-induced OAB in human clinical trial and rat model. The ovariectomized (OVX) for 12 months Sprague–Dawley rat model mimicking the physiological condition of menopause was utilized to induce OAB and assess the potential therapeutic mechanism of LiESWT (0.12 mJ/mm², 300 pulses, and 3 pulses/second). The randomized, single-blinded clinical trial was enrolled 58 participants to investigate the therapeutic efficacy of LiESWT (0.25 mJ/mm², 3000 pulses, 3 pulses/second) on postmenopausal women with OAB. The results revealed that 8 weeks’ LiESWT inhibited interstitial fibrosis, promoted cell proliferation, enhanced angiogenesis protein expression, and elevated the protein phosphorylation of ErK1/2, P38, and Akt, leading to decreased urinary frequency, nocturia, urgency, urgency incontinence, and post-voided residual urine volume, but increased voided urine volume and the maximal flow rate of postmenopausal participants. In conclusion, LiESWT attenuated inflammatory responses, increased angiogenesis, and promoted proliferation and differentiation, thereby improved OAB symptoms, thereafter promoting social activity and the quality of life of postmenopausal participants.

Autophagy Alters Bladder Angiogenesis and Improves Bladder Hyperactivity in the Pathogenesis of Ketamine-Induced Cystitis in a Rat Model

Simple Summary

Long-term ketamine abuse may increase urinary frequency, nocturia, urgency, bladder pain, dysuria, and sometimes hematuria. Evaluation of the pathophysiological mechanism of bladder voiding dysfunction in ketamine-induced cystitis (KIC) patients is a critical step for therapy. This study uses autophagy inducer (rapamycin, mTOR inhibitor) and inhibitor (wortmannin, PI3K-III inhibitor) to identify the role of autophagy in bladder angiogenesis alteration and bladder hyperactivity improvement.

Abstract

The present study attempts to elucidate whether autophagy alters bladder angiogenesis, decreases inflammatory response, and ameliorates bladder hyperactivity—thereby influencing bladder function in ketamine-induced cystitis (KIC). In our methodology, female Sprague-Dawley (S-D) rats were randomly divided into the control group, the ketamine group, the ketamine+rapamycin group, and the ketamine+wortmannin group. The bladder function, contractile activity of detrusor smooth muscle, distribution of autophagosome and autolysosome, total white blood cells (WBCs) and leukocyte differential counts, the expressions of autophagy-associated protein, angiogenesis markers, and signaling pathway molecules involved in KIC were tested, respectively. The data revealed that treatment with ketamine significantly results in bladder overactivity, enhanced interstitial fibrosis, impaired endothelium, induced eosinophil-mediated inflammation, swelling, and degraded mitochondria and organelles, inhibited angiogenesis, and elevated the phosphorylation of Akt. However, treatment with rapamycin caused an inhibitory effect on vascular formation, removed ketamine metabolites, decreased the eosinophil-mediated inflammation, and ameliorated bladder hyperactivity, leading to improve bladder function in KIC. Moreover, wortmannin treatment reduced basophil-mediated inflammatory response, improved bladder angiogenesis by increasing capillary density and VEGF expression, to reverse antiangiogenic effect to repair KIC. In conclusion, these findings suggested that autophagy could modulate inflammatory responses and angiogenesis, which improved bladder function in KIC.

Vascular endothelial growth factor and pigment epithelial-derived factor in the peripheral response to ketamine

BACKGROUND

Ketamine is a rapid-acting antidepressant but its mechanism remains unclear. Vascular endothelial growth factor growth factor (VEGF) has been reported in the antidepressant action of ketamine in rodents. VEGF and pigment epithelial-derived factor (PEDF) signalling are closely linked and both are dysregulated in depression. We explored the effect of a single infusion of ketamine, with midazolam as comparison, on peripheral whole blood mRNA levels of vascular endothelial growth factor A (VEGFA) and PEDF, and the VEGFA/PEDF ratio, in patients with depression.

METHODS

Twenty-five patients with depression were randomised to either ketamine (0.5 mg/kg) or midazolam (0.045 mg/kg) infusions over 40 min. Blood plasma samples were taken 1 h before the first infusion and 4 h after the infusion start. mRNA was extracted and qRT-PCR performed to analyse gene expression.

RESULTS

Single infusions of ketamine and midazolam both decreased depression scores (F(1,21) = 102.40, p < 0.000). There was a significant group × time interaction for VEGFA mRNA levels (F(1, 21) = 5.207, p = 0.029), with ketamine increasing VEGFA levels. There was no significant effect of either ketamine or midazolam on PEDF levels. There was a significant group × time interaction for VEGFA/PEDF mRNA ratio, with ketamine alone increasing this ratio (F(1, 11) = 12.085, p = 0.005).

LIMITATIONS

Patients were on psychotropic medication and continued treatment as usual throughout the study.

CONCLUSIONS

These preliminary results support a role for VEGF in the action of ketamine and suggest a novel role for VEGF/PEDF in the molecular response to ketamine.

Elevated serum vascular endothelial growth factor in treatment-resistant schizophrenia treated with electroconvulsive therapy: Positive association with therapeutic effects

OBJECTIVES

As the name implies, vascular endothelial growth factor (VEGF) enhances angiogenesis, promotes vascular permeability, and stimulates neurogenesis in the adult brain. Furthermore, animal model studies have shown that electroconvulsive therapy (ECT), which is primarily utilised in cases of treatment-resistant schizophrenia (TRS), regulates the expression of VEGF. The current study focuses largely on the effect of ECT on VEGF serum concentration, and the relationship between VEGF and therapeutic effects in patients diagnosed with TRS.

METHODS

Participants comprised 40 TRS patients and 43 healthy controls. Clinical severity was assessed (i.e. 1 day before commencement of ECT and 1 day following ECT) using the positive and negative syndrome scale (PANSS). Blood samples were also collected for VEGF measurements at corresponding time points.

RESULTS

Pre-treatment serum VEGF levels were significantly lower in TRS patients compared to healthy controls. VEGF concentrations increased significantly following ECT, whereas no difference was found in controls. Moreover, there was a positive correlation between the change in VEGF and therapeutic effects.

CONCLUSIONS

Elevated serum VEGF in TRS treated with ECT is positively associated with therapeutic effects, suggesting that alterations in VEGF levels may constitute an index by which to evaluate the improvement in clinical condition.

Altered serum levels of vascular endothelial growth factor in first-episode drug-naïve and chronic medicated schizophrenia

There is much evidence of a relationship between alterations in the brain's regional cellular energy metabolism and blood flow in schizophrenic. Vascular endothelial growth factor (VEGF) plays a role in the pathogenesis of neuropsychiatric illnesses. So, we compared serum VEGF levels in drug-naïve first-episode psychotic (FEP) and chronically medicated schizophrenic to examine if a correlation existed between VEGF and psychopathological symptoms. The serum VEGF levels were assessed in 46 FEP patients, 47 chronic medicated patients and 50 healthy controls. Symptoms of schizophrenia were evaluated with the Positive and Negative Syndrome Scale (PANSS) and sandwich enzyme-linked immunosorbent assay (ELISA) was used to measure serum VEGF levels. VEGF levels were significantly lower in FEP patients compared to both chronically medicated schizophrenic patients and healthy controls, while VEGF levels in chronically medicated patients were markedly higher than in healthy controls. Furthermore, a significant correlation was detected between the levels and the PANSS negative subscale among patient groups. However, no significant correlation was observed between VEGF and clinical variables in patients. This study suggested that imbalanced neurotrophic factors may be associated with the onset of schizophrenia, but subsequent increased VEGF may be related to medication or other factors in disease progression.

Baseline serum vascular endothelial growth factor levels predict treatment response to antipsychotic medication in patients with schizophrenia

Vascular endothelial growth factor (VEGF) is implicated in angiogenesis, blood flow, and neuroplasticity, which have previously been shown to contribute to schizophrenia and the mechanisms of action of antipsychotic medication. The aim of the present study was to investigate whether baseline serum VEGF levels predict treatment responses to antipsychotic medication. Drug-free adults with schizophrenia were administered monotherapy with atypical antipsychotic drugs for 6 weeks. Participants' psychiatric symptoms were assessed using the positive and negative symptom scale (PANSS) before and after treatment. Blood samples for VEGF measurements were collected from 201 participants comprising 83 healthy controls and 118 patients (i.e. only on admission). Baseline VEGF levels in adults with schizophrenia were significantly lower than those in the control group (t = 3.656, df = 199, P < 0.001). In particular, pretreatment VEGF levels were significantly higher in patients responding to drug treatment at follow-up (≥ 50% reduction in initial PANSS total) (t = 4.743, df = 116, P < 0.001). The predictive power of serum VEGF levels was investigated using receiver operating characteristic curves. The area under the curve was 0.774 (95% confidence interval 0.688-0.846); for fixed specificity of 78.8%, the corresponding sensitivity was 63.5%. Results from this preliminary experiment suggest high baseline serum concentrations of VEGF may predict a better response to antipsychotic medications in adults with schizophrenia. Further studies using larger sample sizes are needed to verify the findings.

Low serum level of epidermal growth factor in chronic ketamine users

BACKGROUND

Growth factors play an important role in brain development. Whether epidermal growth factor (EGF) plays a role in the pathophysiology of ketamine related disorders is unexplored. In this study, we examined the serum levels of EGF in chronic ketamine users as compared with healthy controls. The possible correlation between serum EGF levels with the demographic, ketamine use characteristics and psychopathological symptoms were analyzed.

METHODS

Sixty-seven chronic ketamine users and 40 healthy subjects were recruited. Serum EGF levels were measured by enzyme-linked immunosorbent assay. Psychopathological symptoms were assessed using Positive and Negative Syndrome Scale, Beck Depression Inventory and Beck Anxiety Inventory.

RESULTS

The serum level of EGF in the chronic ketamine users was significantly lower than that of healthy subjects (22.34 ± 4.81 pg/ml vs. 87.10 ± 2.96 pg/ml, F = 15.169, p < 0.01). The serum EGF level was negatively correlated with the current average dose of ketamine consumption per day of use (p = 0.015), and positively associated with the Positive and Negative Syndrome Scale positive symptom score (p = .022).

CONCLUSIONS

Serum level of EGF decreased in chronic ketamine users compared with healthy subjects, which may play a role in the pathophysiology of ketamine related disorders.