Protective Role of L-3-n-Butylphthalide in Cognitive Function and Dysthymic Disorders in Mouse With Chronic Epilepsy

DL-3-n-Butylphthalide Ameliorates Post-stroke Emotional Disorders by Suppressing Neuroinflammation and PANoptosis

Post-stroke emotional disorders such as post-stroke anxiety and post-stroke depression are typical symptoms in patients with stroke. They are closely associated with poor prognosis and low quality of life. The State Food and Drug Administration of China has approved DL-3-n-butylphthalide (NBP) as a treatment for ischemic stroke (IS). Clinical research has shown that NBP alleviates anxiety and depressive symptoms in patients with IS. Therefore, this study explored the role and molecular mechanisms of NBP in cases of post-stroke emotional disorders using network pharmacology and experimental validation. The results showed that NBP treatment significantly increased the percentage of time spent in the center of the middle cerebral artery occlusion (MCAO) rats in the open field test and the percentage of sucrose consumption in the sucrose preference test. Network pharmacology results suggest that NBP may regulate neuroinflammation and cell death. Further experiments revealed that NBP inhibited the toll-like receptor 4/nuclear factor kappa B signaling pathway, decreased the level of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6, and M1-type microglia markers (CD68, inducible nitric oxide synthase), and reduced the expression of PANoptosis-related molecules including caspase-1, caspase-3, caspase-8, gasdermin D, and mixed lineage kinase domain-like protein in the hippocampus of the MACO rats. These findings demonstrate that the mechanisms through which NBP ameliorates post-stroke emotional disorders in rats are associated with inhibiting neuroinflammation and PANoptosis, providing a new strategy and experimental basis for treating post-stroke emotional disorders.

Inhibition of neuronal pentraxin 2 relieved epileptic seizure via reducing GluA1 phosphorylation

Neuronal pentraxin 2 (Nptx2), a member of the synaptic protein family linked to excitatory synaptic formation, is found to be upregulated in epileptic mice, yet its role in epilepsy has been unclear. In vivo, we constructed a mouse model of epilepsy by using kainic acid induction. In vitro experiments, a Mg2+-free medium was used to induce epileptiform discharges in neurons. The results showed that the Nptx2 was upregulated in epileptic mice. Moreover, Nptx2 knockdown reduced the number of seizures and seizure duration. Knocking down Nptx2 not only reduced the number and duration of seizures but also showed a decrease in electroencephalogram amplitude. Behavioral tests indicated improvements in learning and memory abilities after Nptx2 knockdown. The Nissl staining and Timms staining revealed that Nptx2 silencing mitigated epilepsy-induced brain damage. The immunofluorescence staining revealed that Nptx2 absence resulted in a reduction of apoptosis. Nptx2 knockdown reduced Bax, cleaved caspase3, and cleaved caspase9 expression, while increased Bcl-2 expression. Notably, Nptx2 knockdown inhibited GluA1 phosphorylation at the S831 site and reduced the GluA1 membrane expression. The PSD95 expression declined in the epilepsy model, while the Nptx2 knockdown reversed it. Collectively, our study indicated that Nptx2 silencing not only alleviated brain damage and neuron apoptosis but also improved learning and memory ability in epileptic mice, suggesting Nptx2 as a promising target for epilepsy treatment.

Neurological Applications of Celery (Apium graveolens): A Scoping Review

Apium graveolens is an indigenous plant in the family Apiaceae, or Umbelliferae, that contains many active compounds. It has been used traditionally to treat arthritic conditions, gout, and urinary infections. The authors conducted a scoping review to assess the quality of available evidence on the overall effects of celery when treating neurological disorders. A systematic search was performed using predetermined keywords in selected electronic databases. The 26 articles included upon screening consisted of 19 in vivo studies, 1 published clinical trial, 4 in vitro studies and 2 studies comprising both in vivo and in vitro methods. A. graveolens and its bioactive phytoconstituent, 3-n-butylphthalide (NBP), have demonstrated their effect on neurological disorders such as Alzheimer's disease, Parkinson's disease, stroke-related neurological complications, depression, diabetes-related neurological complications, and epilepsy. The safety findings were minimal, showing that NBP is safe for up to 18 weeks at 15 mg/kg in animal studies, while there were adverse effects (7%) reported when consuming NBP for 24 weeks at 600 mg daily in human trials. In conclusion, the safety of A. graveolens extract and NBP can be further investigated clinically on different neurological disorders based on their potential role in different targeted pathways.

Beneficial effects of celery seed extract (Apium graveolens), as a supplement, on anxiety and depression in hypertensive patients: a randomized clinical trial

BACKGROUND

Anxiety and depression are crucial public health issues, affecting the rising in hospitalizations and death. Anxiety and depression can worsen hypertension and vice versa.

OBJECTIVE

The current study has investigated the effects of celery seed extract, as a drug supplement, with the active ingredient of 3-n-butylphthalide, on mental problems primarily anxiety and secondary depression in hypertensive patients.

DESIGN

The current study was a randomized, triple-blind, placebo-controlled, cross-over, 4-week clinical trial with a 4-week washout period. Fifty hypertensive patients received 4 placebo or celery seed extract capsules (1.34 g per day) for 4 weeks as a supplement to their usual medication regimen. The blood pressure parameters were assessed using 24-h ambulatory blood pressure monitoring device. Anxiety and depression and their wide range of symptoms were evaluated using Beck anxiety and depression inventories (BAI and BDI).

RESULTS

In the celery treatment step, the mean reduction in BAI and BDI scores were 6.78 (P < 0.001) and 3.63 (P < 0.01), respectively. Some symptoms of anxiety including unable to relax, nervousness, numbness, dizziness, flushed face, sweating, and breathing difficulty were significantly improved by celery consumption (P < 0.001). Celery could decrease symptoms of depression such as sadness, crying, loss of energy, insomnia, irritability, fatigue, loss of interest in sex, and punishment feeling (P < 0.01). The mean reduction in blood pressure parameters was also significant during celery therapy (P < 0.001).

CONCLUSIONS

The psychometric properties of anxiety and depression were investigated and the results were promising. The results indicated the anti-anxiety and anti-depressive properties of celery seed extract as a supplement in hypertensive patients.

CLINICAL TRIAL REGISTRATION

Registry name: Iranian Registry of Clinical Trials (IRCT), Registration number: IRCT20130418013058N8, Registration link: https://www.irct.ir/trial/30021 . The study was carried out between 2018-09-21 and 2020-07-20.

Neurotransmitters and molecular chaperones interactions in cerebral malaria: Is there a missing link?

Plasmodium falciparum is responsible for the most severe and deadliest human malaria infection. The most serious complication of this infection is cerebral malaria. Among the proposed hypotheses that seek to explain the manifestation of the neurological syndrome in cerebral malaria is the vascular occlusion/sequestration/mechanic hypothesis, the cytokine storm or inflammatory theory, or a combination of both. Unfortunately, despite the increasing volume of scientific information on cerebral malaria, our understanding of its pathophysiologic mechanism(s) is still very limited. In a bid to maintain its survival and development, P. falciparum exports a large number of proteins into the cytosol of the infected host red blood cell. Prominent among these are the P. falciparum erythrocytes membrane protein 1 (PfEMP1), P. falciparum histidine-rich protein II (PfHRP2), and P. falciparum heat shock proteins 70-x (PfHsp70-x). Functional activities and interaction of these proteins with one another and with recruited host resident proteins are critical factors in the pathology of malaria in general and cerebral malaria in particular. Furthermore, several neurological impairments, including cognitive, behavioral, and motor dysfunctions, are known to be associated with cerebral malaria. Also, the available evidence has implicated glutamate and glutamatergic pathways, coupled with a resultant alteration in serotonin, dopamine, norepinephrine, and histamine production. While seeking to improve our understanding of the pathophysiology of cerebral malaria, this article seeks to explore the possible links between host/parasite chaperones, and neurotransmitters, in relation to other molecular players in the pathology of cerebral malaria, to explore such links in antimalarial drug discovery.

Klotho alleviates NLRP3 inflammasome-mediated neuroinflammation in a temporal lobe epilepsy rat model by activating the Nrf2 signaling pathway

Neuroinflammation not only contributes to epileptogenesis and neurodegeneration, but is also associated with cognitive impairment. Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated neuroinflammation is positively correlated with progression of temporal lobe epilepsy (TLE) and cognitive impairment. Recent studies have shown that the anti-aging protein, klotho, exerts anti-neuroinflammation effects and enhances cognition in neurodegenerative disorders. In the present study, we investigated the role and underlying mechanism of klotho action in NLRP3 inflammasome-mediated neuroinflammation in a TLE model. Specifically, we first injected an adeno-associated viral (AAV)-mediated overexpression of klotho (AAV-KL) into the bilateral hippocampus of rats. After 3 weeks, rats were intraperitoneally injected with lithium-chloride pilocarpine (LiCl-Pilo) to generate a TLE model. Results showed that klotho was significantly downregulated six weeks after TLE, while AAV-mediated klotho overexpression substantially attenuated TLE-induced hippocampal neuronal injury and cognitive impairment. Interestingly, klotho overexpression significantly alleviated expression of NLRP3, IL-1β, and caspase-1 proteins, but up-regulated activation of nuclear factor erythroid 2-related factor 2 (Nrf2). However, treatment with Nrf2 inhibitor ML385 significantly reversed klotho's beneficial effects, including alleviated neuroinflammation, attenuated neuronal injury, and improved cognitive function. Taken together, these results indicated that klotho alleviated NLRP3 inflammasome-mediated neuroinflammation by activating the Nrf2 signaling pathway in the TLE rat model, suggesting that this the anti-aging protein could be a novel and promising therapeutic agent for managing TLE-associated cognitive impairment.

DL-3-n-butylphthalide promotes hippocampal neurogenesis and reduces mossy fiber sprouting in chronic temporal lobe epilepsy rats

Background

A decrease in hippocampal neurogenesis is considered an important cause of cognitive impairment, while changes in mossy fiber sprouting are closely related to development of spontaneous recurrent seizures in chronic temporal lobe epilepsy (TLE). Racemic l-3-n-butylphthalide (DL-NBP) can alleviate cognitive impairment in ischemic stroke and Alzheimer’s disease by promoting neurogenesis. DL-NBP treatment can also improve cognitive function and reduce seizure incidence in chronic epileptic mice. However, the mechanisms of action of DL-NBP remain unclear. The aim of the present study was to examine the effects of DL-NBP on mossy fiber sprouting, hippocampal neurogenesis, spontaneous epileptic seizures, and cognitive functioning in the chronic phase of TLE.

Methods

Nissl staining was used to evaluate hippocampal injury, while immunofluorescent staining was used to analyze hippocampal neurogenesis. The duration of spontaneous seizures was measured by electroencephalography. The Morris water maze was used to evaluate cognitive function. Timm staining was used to assess mossy fiber sprouting.

Results

TLE animals showed reduced proliferation of newborn neurons, cognitive dysfunction, and spontaneous seizures. Treatment with DL-NBP after TLE increased the proliferation and survival of newborn neurons in the dentate gyrus, reversed the neural loss in the hippocampus, alleviated cognitive impairments, and decreased mossy fiber sprouting and long-term spontaneous seizure activity.

Conclusions

We provided pathophysiological and morphological evidence that DL-NBP might be a useful therapeutic for the treatment of TLE.

Klotho ameliorated cognitive deficits in a temporal lobe epilepsy rat model by inhibiting ferroptosis

Cognitive deficits are among the most common comorbidities of temporal lobe epilepsy (TLE). Ferroptosis associated with the accumulation of iron overload-dependent lipid peroxidation produces significant cognitive deficits in TLE. The anti-aging protein, klotho, has been shown to exert neuroprotective effects while enhancing cognition in neurodegenerative disorders. However, the role of klotho in TLE progression has not been established. In this study, we evaluated the effects and underlying mechanisms of klotho in a rat model of TLE induced by lithium-chloride and pilocarpine (LiCl-Pilo). The expression of klotho was found to be inhibited in the hippocampus following LiCl-Pilo induced TLE in rats. An adeno-virus (AAV), which mediated klotho overexpression (AAV-KL) was injected into the bilateral hippocampus of the rat models. After 3 weeks, rats were treated through intraperitoneal injections of LiCl-Pilo. After 9 weeks, AAV-KL was found to have significantly induced klotho overexpression in the hippocampus, effectively ameliorated cognitive deficits and exerted neuroprotective effects in LiCl-Pilo induced TLE rat models. Klotho significantly prevented ferroptosis and iron overload. Meanwhile, klotho regulated the expressions of divalent metal transporter 1 (DMT 1) and ferroportin (FPN) that were associated with iron accumulation in the hippocampus. Furthermore, klotho significantly elevated glutathione peroxidase-4 (GPX-4) and glutathione (GSH) levels while suppressed reactive oxygen species (ROS) levels. In conclusion, klotho ameliorated cognitive deficits and exerted neuroprotective effects by inhibiting ferroptosis in LiCl-Pilo induced TLE rat models.

Efficacy of sequential N-butylphthalide therapy on psychiatric and behavioral functions in acute ischemic stroke

BACKGROUND

Stroke can cause physical and mental problems. This study examined how the sequential therapy of N-butylphthalide (NBP) could effectively improve physical movement, life activities, and psychological disorders in stroke patients.

METHODS

This double-blind, randomized controlled trial included middle-aged or elderly patients with acute ischemic stroke that had commenced within 48 hours before enrolment in the study. The experimental group was administered 100 mL NBP injections twice a day in the first 14 days, and a sequential 200 mg NBP soft capsule 3 times a day for the next 76 days. The control group was administered 100 mL NBP placebo injections twice a day in the first 14 days and 200 mg sequential NBP placebo soft capsule 3 times a day for the next 76 days. Primary outcomes were the National Institutes of Health Stroke Scale, the Barthel Index of activities of daily living, and Modified Rankin Scale which were evaluated at day 0, day 14, and month 1 or at day 14, month 3, and month 6. Secondary outcomes included the Hamilton Anxiety Scale and the Hamilton Depression Scale, all were evaluated on day 0, month 3, and month 6. Moreover, the adverse reaction of NBP or other serious adverse events were evaluated at each time.

RESULTS

Our therapy significantly increased the Barthel Index of activities of daily living scores, decreased the National Institutes of Health Stroke Scale and Modified Rankin Scale scores, and the incidence of the Hamilton Anxiety Scale and the Hamilton Depression Scale of ischemic stroke patients (P < .05).

CONCLUSION

Our results indicated that 90 days' sequential therapy with NBP as an additional therapy in the treatment of ischemic stroke can better improve patients' psychological and behavioral functions without significant side effects.

DL-3-n-butylphthalide ameliorates diabetes-associated cognitive decline by enhancing PI3K/Akt signaling and suppressing oxidative stress

DL-3-n-Butylphthalide (DL-NBP), a small molecular compound extracted from the seeds of Apium graveolens Linn (Chinese celery), has been shown to exert neuroprotective effects due to its anti-inflammatory, anti-oxidative and anti-apoptotic activities. DL-NBP not only protects against ischemic cerebral injury, but also ameliorates vascular cognitive impairment in dementia patients including AD and PD. In the current study, we investigated whether and how DL-NBP exerted a neuroprotective effect against diabetes-associated cognitive decline (DACD) in db/db mice, a model of type-2 diabetes. db/db mice were orally administered DL-NBP (20, 60, 120 mg· kg-1· d-1) for 8 weeks. Then the mice were subjected to behavioral test, their brain tissue was collected for morphological and biochemical analyses. We showed that oral administration of DL-NBP significantly ameliorated the cognitive decline with improved learning and memory function in Morris water maze testing. Furthermore, DL-NBP administration attenuated diabetes-induced morphological alterations and increased neuronal survival and restored the levels of synaptic protein PSD95, synaptophysin and synapsin-1 as well as dendritic density in the hippocampus, especially at a dose of 60 mg/kg. Moreover, we revealed that DL-NBP administration suppressed oxidative stress by upregulating Nrf2/HO-1 signaling, and increased brain-derived neurotrophic factor (BDNF) expression by activating PI3K/Akt/CREB signaling in the hippocampus. These beneficial effects of DL-NBP were observed in high glucose-treated PC12 cells. Our results suggest that DL-NBP may be a potential pharmacologic agent for the treatment of DACD.

From Seeds of Apium graveolens Linn. to a Cerebral Ischemia Medicine: The Long Journey of 3-n-Butylphthalide

3-n-Butylphthalide (NBP) as well as its derivatives and analogues (NBPs), in racemic or enantiomerically pure forms, possess potent and diverse pharmacological properties and have shown a great potential therapeutic interest for many human conditions, especially for cerebral ischemia. This Perspective outlines the synthesis and therapeutic applications of NBPs.

Depression and Anxiety in the Epilepsies: from Bench to Bedside

PURPOSE OF REVIEW

Depression and anxiety substantially contribute to interictal disability in patients with epilepsy (PWE). This review summarizes current studies that shed light on mechanisms of comorbidity.

RECENT FINDINGS

Mounting epidemiological data implicate shared risk factors for anxiety/depression and seizure propensity, but these remain largely elusive and probably vary by epilepsy type. Within PWE, these symptoms appear to be associated with unique genetic, neuropathological, and connectivity profiles. Temporal lobe epilepsy has received enormous emphasis particularly in preclinical studies of comorbidity, where candidate neurobiological mechanisms underlying bidirectionality have been tested without psychopharmacological confounds. Depression and anxiety in epilepsy reflect dysfunction within broadly distributed limbic networks that may be the cause or consequence of epileptogenesis. In refractory epilepsy, seizures and/or certain anticonvulsants may distort central emotional homeostatic mechanisms that perpetually raise seizure risk. Developing future safe and effective combined anticonvulsant-antidepressant treatments will require a detailed understanding of anatomical and molecular nodes that pleiotropically enhance seizure risk and negatively alter emotionality.

The Efficacy of N-Butylphthalide and Dexamethasone Combined with Hyperbaric Oxygen on Delayed Encephalopathy After Acute Carbon Monoxide Poisoning

Background

Carbon monoxide (CO) poisoning is a common health problem among people in many countries, primarily because of its severe clinical effects and high toxicological morbidity and mortality. Acute brain injury and delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) are the most common neurological complications. This study was performed to assess the efficacy of N-butylphthalide (NBP) and dexamethasone (DXM) combined with hyperbaric oxygen (HBO) in patients with DEACMP.

Patients and Methods

A total of 171 patients with DEACMP were recruited and assigned to the combined therapy group (receiving NBP and DXM 5 mg/day plus HBO therapy) or the control group (HBO therapy as monotherapy). Conventional treatments were provided for all patients. The cognition and movement changes in patients were evaluated by the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA) scale and the Barthel index of activities of daily living (ADL) before and after the treatment at 1 month, 3 months, and 1 year, respectively.

Results

At 1 month, 3 months, and 1 year after the treatment, the MMSE, MoCA and ADL scores were all significantly higher in the combined therapy group than those in the control group. There were no significant alterations in blood glucose, blood lipids, or liver and kidney function during the whole treatment session. Some patients experienced loss of appetite, mild headache and minor skin irritations. However, these patients recovered by themselves and needed no additional medications or special treatment.

Conclusion

These results indicated that NBP and DXM combined with HBO for the treatment of DEACMP can significantly improve the cognitive and motor functions of patients and is very safe.

Dl-3n-butylphthalide improves traumatic brain injury recovery via inhibiting autophagy-induced blood-brain barrier disruption and cell apoptosis

Blood-brain barrier (BBB) disruption and neuronal apoptosis are important pathophysiological processes after traumatic brain injury (TBI). In clinical stroke, Dl-3n-butylphthalide (Dl-NBP) has a neuroprotective effect with anti-inflammatory, anti-oxidative, anti-apoptotic and mitochondrion-protective functions. However, the effect and molecular mechanism of Dl-NBP for TBI need to be further investigated. Here, we had used an animal model of TBI and SH-SY5Y/human brain microvascular endothelial cells to explore it. We found that Dl-NBP administration exerts a neuroprotective effect in TBI/OGD and BBB disorder, which up-regulates the expression of tight junction proteins and promotes neuronal survival via inhibiting mitochondrial apoptosis. The expressions of autophagy-related proteins, including ATG7, Beclin1 and LC3II, were significantly increased after TBI/OGD, and which were reversed by Dl-NBP treatment both in vivo and in vitro. Moreover, rapamycin treatment had abolished the effect of Dl-NBP for TBI recovery. Collectively, our current studies indicate that Dl-NBP treatment improved locomotor functional recovery after TBI by inhibiting the activation of autophagy and consequently blocking the junction protein loss and neuronal apoptosis. Dl-NBP, as an anti-inflammatory and anti-oxidative drug, may act as an effective strategy for TBI recovery.

Reduced Acoustic Startle Response and Prepulse Inhibition in the Tg4-42 Model of Alzheimer's Disease

Sensorimotor deficits have been described in several neuropsychiatric disorders including Alzheimer’s disease. The aim of the present study was to evaluate possible sensorimotor gating deficits in the Tg4-42 mouse model of Alzheimer’s disease using the prepulse inhibition task (PPI). Previous studies indicated that the hippocampus is essentially involved in the regulation of PPI. We analyzed 7-month-old homozygous Tg4-42 mice as mice at this age display severe neuron loss especially in the CA1 region of the hippocampus. Our results revealed a reduced startle response and PPI in Tg4-42 mice. The observed deficits in startle response and PPI are likely due to altered sensory processing abilities rather than hearing deficits as Tg4-42 displayed intact hearing in the fear conditioning task. The present study demonstrates for the first time that sensorimotor gating is impaired in Tg4-42 mice. Analyzing startle response as well as the PPI may offer valuable measurements to assess the efficacy of therapeutic strategies in the future in this Alzheimer’s disease model.

Application and prospects of butylphthalide for the treatment of neurologic diseases

OBJECTIVE

The 3-N-butylphthalide (NBP) comprises one of the chemical constituents of celery oil. It has a series of pharmacologic mechanisms including reconstructing microcirculation, protecting mitochondrial function, inhibiting oxidative stress, inhibiting neuronal apoptosis, etc. Based on the complex multi-targets of pharmacologic mechanisms of NBP, the clinical application of NBP is increasing and more clinical researches and animal experiments are also focused on NBP. The aim of this review was to comprehensively and systematically summarize the application of NBP on neurologic diseases and briefly summarize its application to non-neurologic diseases. Moreover, recent progress in experimental models of NBP on animals was summarized.

DATA SOURCES

Literature was collected from PubMed and Wangfang database until November 2018, using the search terms including "3-N-butylphthalide," "microcirculation," "mitochondria," "ischemic stroke," "Alzheimer disease," "vascular dementia," "Parkinson disease," "brain edema," "CO poisoning," "traumatic central nervous system injury," "autoimmune disease," "amyotrophic lateral sclerosis," "seizures," "diabetes," "diabetic cataract," and "atherosclerosis."

STUDY SELECTION

Literature was mainly derived from English articles or articles that could be obtained with English abstracts and partly derived from Chinese articles. Article type was not limited. References were also identified from the bibliographies of identified articles and the authors' files.

RESULTS

NBP has become an important adjunct for ischemic stroke. In vascular dementia, the clinical application of NBP to treat severe cognitive dysfunction syndrome caused by the hypoperfusion of brain tissue during cerebrovascular disease is also increasing. Evidence also suggests that NBP has a therapeutic effect for neurodegenerative diseases. Many animal experiments have found that it can also improve symptoms in other neurologic diseases such as epilepsy, cerebral edema, and decreased cognitive function caused by severe acute carbon monoxide poisoning. Moreover, NBP has therapeutic effects for diabetes, diabetes-induced cataracts, and non-neurologic diseases such as atherosclerosis. Mechanistically, NBP mainly improves microcirculation and protects mitochondria. Its broad pharmacologic effects also include inhibiting oxidative stress, nerve cell apoptosis, inflammatory responses, and anti-platelet and anti-thrombotic effects.

CONCLUSIONS

The varied pharmacologic mechanisms of NBP involve many complex molecular mechanisms; however, there many unknown pharmacologic effects await further study.

L-3-n-butylphthalide soft capsules in the treatment of Parkinson disease dementia: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

In recent years, L-3-n-butylphthalide (L-NBP) has been used for Parkinson disease dementia (PDD) to attenuate cognitive impairments in China. Therefore, we selected published and qualified clinical trials to conduct a systematic review and meta-analysis with the aim of assessing the effectiveness and safety of L-NBP in the treatment of PDD.

OBJECTIVE

This systematic review and meta-analysis aimed to assess the effectiveness and safety of L-NBP in the treatment of PDD.

METHODS

We searched PubMed, EMBASE, China National Knowledge Infrastructure, Chinese Scientific Journal Database (VIP database), and Wan-Fang Database to collect eligible articles. We calculated pooled estimates of odds ratios or the standard mean deviation with 95% confidence intervals.

RESULTS

Eight randomized controlled trials were included in our meta-analysis. Our meta-analysis showed that L-NBP combined with Western medicine (WM) had a better effect on improving cognitive dysfunction, the total effective rate, symptoms of Parkinson disease (PD), and activities of daily living function than WM alone. Regarding safety, no serious adverse events were observed in the experimental group.

CONCLUSION

We found that L-NBP as a complementary therapy may have a positive therapeutic effect for improving cognitive dysfunction, the total effective rate, symptoms of PD, quality of life, and the related serum factors in the treatment of PDD. Furthermore, L-NBP was a safe treatment for PDD. However, the findings of our meta-analysis may be influenced by the low quality of the included studies. We highlight the need to conduct trials with higher methodological quality.