Recent progress in therapeutic strategies for microglia-mediated neuroinflammation in neuropathologies

Introduction: Chronic activation of microglia is the hallmark of numerous neuropathologies such as Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. The activated microglia perpetuate inflammation by releasing an array of pro-inflammatory and neurotoxic factors, which eventually exacerbate neurotoxicity and neurodegeneration upon chronic activation of these cells. However, under acute conditions, activated microglia elicit pro-inflammatory as well as anti-inflammatory responses that are associated with neuroprotection. Given the role of microglia in neuroinflammation, recent studies have attempted to unravel the mechanisms that aid to establish microglial cell-based therapy.

Areas covered: While total suppression of microglial activation may compromise its beneficial role in tissue repair in the aftermath of an insult, the benefits of modulating microglial activation and promoting microglia polarization to a neuroprotective phenotype have been highlighted recently.

Expert opinion: So far, the therapeutic strategy focussed on neutralizing microglia-mediated neuroinflammation using drugs that block the release of pro-inflammatory mediators has limitations, such as unwarranted side effects. Recent advances reveal several alternative molecular targets and potential epi-drugs that are capable of modulating microglial function and promoting neuroprotection. This review discusses the recent progress made in understanding the mechanisms of microglia-mediated neuroinflammation in various neuropathologies, and the emerging anti-inflammatory therapeutic strategies in this field.     

Congenital lacrimal sac fistula: intraoperative visualization by polyvinyl siloxane cast

We report the intraoperative use of polyvinyl siloxane impression material to demonstrate the anatomy of the lacrimal sac, canaliculi, and lacrimal duct in a case of congenital lacrimal sac fistula. A 1-week-old boy was examined for tearing since birth. Examination revealed a left congenital lacrimal sac fistula. After a failed surgery to close the fistula with silicone intubation at 6 months of age, the patient underwent endonasal dacryocystorhinostomy performed at 14 months of age, aided by intraoperative injection of polyvinyl siloxane (trade name Reprosil) to mark and protect the nasolacrimal sac and facilitate endonasal visualization. A polyvinyl siloxane cast demonstrated the anatomy of the accessory canaliculus causing nasolacrimal duct obstruction. Postoperatively, the epiphora resolved and the fistula remained closed. The polyvinyl siloxane cast provides a 3-dimensional "ex vivo " model of the lacrimal sac, upper duct, and canalicular anatomy, and can be used in dacryocystorhinostomy surgery to identify and protect the lacrimal sac.     

Lifitegrast clinical efficacy for treatment of signs and symptoms of dry eye disease across three randomized controlled trials

Objective: Report efficacy findings from three clinical trials (one phase 2 and two phase 3 [OPUS-1, OPUS-2]) of lifitegrast ophthalmic solution 5.0% for treatment of dry eye disease (DED).

Research design and methods: Three 84-day, randomized, double-masked, placebo-controlled trials. Adults (≥18 years) with DED were randomized (1:1) to lifitegrast 5.0% or matching placebo. Changes from baseline to day 84 in signs and symptoms of DED were analyzed.

Main outcome measures: Phase 2, pre-specified endpoint: inferior corneal staining score (ICSS; 0–4); OPUS-1, coprimary endpoints: ICSS and visual-related function subscale (0–4 scale); OPUS-2, coprimary endpoints: ICSS and eye dryness score (EDS, VAS; 0–100).

Results: Fifty-eight participants were randomized to lifitegrast 5.0% and 58 to placebo in the phase 2 trial; 293 to lifitegrast and 295 to placebo in OPUS-1; 358 to lifitegrast and 360 to placebo in OPUS-2. In participants with mild-to-moderate baseline DED symptomatology, lifitegrast improved ICSS versus placebo in the phase 2 study (treatment effect, 0.35; 95% CI, 0.05–0.65; p?=?0.0209) and OPUS-1 (effect, 0.24; 95% CI, 0.10–0.38; p?=?0.0007). Among more symptomatic participants (baseline EDS ≥40, recent artificial tear use), lifitegrast improved EDS versus placebo in a post hoc analysis of OPUS-1 (effect, 13.34; 95% CI, 2.35–24.33; nominal p?=?0.0178) and in OPUS-2 (effect, 12.61; 95% CI, 8.51–16.70; p?<?0.0001).

Limitations: Trials were conducted over 12 weeks; efficacy beyond this period was not assessed.

Conclusions: Across three trials, lifitegrast improved ICSS in participants with mild-to-moderate baseline symptomatology in two studies, and EDS in participants with moderate-to-severe baseline symptomatology in two studies. Based on the overall findings from these trials, lifitegrast shows promise as a new treatment option for signs and symptoms of DED.     

Prognostic Nutritional Index and Clinical Response in Locally Advanced Cervical Cancer

Abstract

Background: The prognostic nutritional index (PNI), a marker of immune-nutrition balance, has predictive value in the survival and prognosis of various cancers. However, the impact of PNI on response to chemoradiation is poorly understood.

Materials and Methods: A total of 583 women with locally advanced cervical cancer from two centers were clinically assessed for complete response after chemoradiation. The baseline PNI was individually recorded, and the significance of association between PNI and complete response was analyzed using logistic regression. ROC (receiver operating characteristics) curves were analyzed to determine the cutoff value of PNI that significantly predicted complete response.

Results: Logistic regression analysis demonstrated that the PNI was significantly associated with complete response following chemo radiation (p?<?0.0001). Analysis of the ROC curve for PNI demonstrated an optimal cut off value of 44.8 (p?<?0.0001, sensitivity 66.7, and specificity 88.5); the area under the ROC curve was 0.813 (Youden’s index J, 0.7519).

Conclusions: The PNI is significantly associated with clinical complete response to chemoradiation in locally advanced cervical cancer. Low baseline PNI may lower the likelihood of complete response after chemoradiation. In particular, those with PNI values below 44 should be carefully monitored during treatment; nutritional interventions may offer benefit in these women.     

Effects of chronic plus acute prolonged stress on measures of coping style, anxiety, and evoked HPA-axis reactivity

Exposure to psychological trauma is the precipitating factor for PTSD. In addition, a history of chronic or traumatic stress exposure is a predisposing risk factor. We have developed a Chronic plus Acute Prolonged Stress (CAPS) treatment for rats that models some of the characteristics of stressful events that can lead to PTSD in humans. We have previously shown that CAPS enhances acute fear responses and impairs extinction of conditioned fear. Further, CAPS reduced the expression of glucocorticoid receptors in the medial prefrontal cortex. In this study we examined the effects of CAPS exposure on behavioral stress coping style, anxiety-like behaviors, and acute stress reactivity of the hypothalamic–pituitary–adrenal (HPA) axis. Male Sprague-Dawley rats were exposed to CAPS treatment, consisting of chronic intermittent cold stress (4 °C, 6 h/day, 14 days) followed on day 15 by a single 1-h session of sequential acute stressors (social defeat, immobilization, swim). After CAPS or control treatment, different groups were tested for shock probe defensive burying, novelty suppressed feeding, or evoked activation of adrenocorticotropic hormone (ACTH) and corticosterone release by an acute immobilization stress. CAPS resulted in a decrease in active burying behavior and an increase in immobility in the shock probe test. Further, CAPS-treated rats displayed increases in the latency to feed in the novelty suppressed feeding test, despite an increase in food intake in the home cage. CAPS treatment also reduced the HPA response to a subsequent acute immobilization stress. These results further validate CAPS treatment as a rat model of relevance to PTSD, and together with results reported previously, suggest that CAPS impairs fear extinction, shifts coping behavior from an active to a more passive strategy, increases anxiety, and alters HPA reactivity, resembling many aspects of human PTSD.     

Multi-walled carbon nanotube-induced inhalation toxicity: Recognizing nano bis-demethoxy curcumin analog as an ameliorating candidate

Human beings and ecosystems are being possibly exposed to CNTs, as there is a rise in global production rate of carbon nanotubes (CNTs). This may affect the health of humans and increases the environmental risk. We have already reported the pulmonary toxicity due to the inhalation of MWCNTs. We claim that a compound with anti-inflammatory and antioxidant activity may ameliorate the CNT-induced toxic effect. With this view, we have investigated the ameliorative effect of intravenously-administered nano bis-demethoxy curcumin analog (NBDMCA) against MWCNTs-induced inhalation toxicity by examining the lung histopathology for inflammatory cell dynamics, pulmonary remodeling and estimating the inflammatory biomarkers in the broncho-alveolar lavage fluid. We observed that NBDMCA could ameliorate the injury as evidenced by the decline in the levels of markers of inflammation, cell damage, and the histopathological changes induced by MWCNTs. We conclude that NBDMCA may be used to reduce the risk of MWCNTs-induced inhalation toxicity.     

Effect of Lithium on Rat Cerebrum Under Different Dietary Protein Regimens

This study was designed to investigate the effects of lithium in adult rat brain under different dietary protein regimens. Lithium as carbonate was given at a dose of 1.1 g/kg diet to female rats fed normal (18% protein), low protein (8% protein), and high protein (30% protein) diets for 30 days. Lithium treatment resulted in a significant decrease in the levels of norepinephrine, dopamine, and serotonin in the cerebrum of the rat brain. Further, administration of lithium to rats fed low protein (LP) and high protein (HP) diets also showed a significant decrease in the levels of norepinephrine and dopamine but caused no significant change in the serotonin concentration. Lithium administration to normal diet, LP, and HP groups resulted in a significant increase in the activities of acetylcholinesterase and monoamine oxidase. Lithium treatment led to decrease in the activity of enzyme Na⁺ K⁺ ATPase in all groups. On the second day, the LP group showed enhanced transfer latency (TL), a dependent variable to study elevated plus-maze test, whereas HP diet went from 34% reduction to normal. On the other hand, lithium administration restored the already enhanced TL in the LP group. The study concludes that lithium treatment to protein-deficient cases may not further aggravate the effects of protein-deficient conditions, but it may afford protection.     

Gender-Specific Associations of Objective and Perceived Neighborhood Characteristics With Body Mass Index and Waist Circumference Among Older Adults in the English Longitudinal Study of Ageing

Objectives. We sought to determine whether objective and perceived neighborhood characteristics are independently associated with obesity indicators among older adults and whether associations differ by gender.Methods. Linear regression was used to examine mutually adjusted associations of objective area-level neighborhood deprivation and perceived individual-level neighborhood disorder in 2002–2003 with body mass index (BMI) and waist circumference (WC) 2 years later among 6297 community-dwelling older adults in the English Longitudinal Study of Ageing.Results. Associations between neighborhood characteristics and obesity indicators were evident for women only. Being in the most deprived quintile of neighborhood deprivation was associated with a BMI that was 1.18 kilograms per meters squared higher (95% confidence interval [CI] = 0.54, 1.83) and a WC that was 2.42 centimeters higher (95% CI = 0.90, 3.94) at follow-up in women after adjustment for baseline health status, socioeconomic factors, and neighborhood disorder. Neighborhood disorder was not independently associated with BMI or WC.Conclusions. Among women, greater objective neighborhood deprivation was independently associated with higher BMI and WC after 2 years. Public efforts to reduce obesity among community-dwelling older women may benefit most from addressing objective residential characteristics, over and above subjective perceptions.Obesity increases the risk of heart disease, type 2 diabetes, stroke, and some types of cancer,1 making it an important condition to prevent and manage for any population. According to 2012 estimates, one third of men and women in England between 65 and 74 years of age are considered obese, the highest percentages of any age group.2 Although in general, levels of obesity (as measured via body mass index [BMI]) decrease after the age of 75 years, levels of abdominal adiposity (as measured via waist circumference [WC]) continue to increase with advancing age, particularly among women.2 With a 39% increase among individuals aged 65 to 84 years and a 106% increase among those older than 85 years expected from 2012 to 2032 in England alone,3,4 it is increasingly important to build a broader understanding of obesity risk at older ages.Obesity may be best understood within the context of its wider environmental influences.5 Older adults may restrict much of their daily life activity to their residential environment, as a result of either retirement or functional limitations, and may consequently be more influenced by these surroundings than younger adults.6 Thus, examining aspects of neighborhood environments may increase our understanding of obesity risk among older adults in particular.Although definitions vary, a neighborhood is broadly regarded as the area immediately surrounding one’s place of residence, measured either objectively at the area level through census data or predefined boundaries, or subjectively at the individual level through self-reported perceptions.7 Objective neighborhood characteristics associated with an individual’s obesity risk include residential density, walkability, presence of graffiti, local access to recreational facilities, presence of green space and supermarkets, and inadequate housing; unfavorable levels of these characteristics may together form a concept known as “neighborhood deprivation.”8,9 Associations between objective neighborhood factors and obesity risk have been shown to be gender-specific. For instance, one study showed that women living in the most deprived areas of the United Kingdom had a higher baseline BMI than those living in the least deprived areas and exhibited greater BMI increases over 13 years,10 whereas these associations were not evident among men.By contrast, subjective neighborhood characteristics may include individual perceptions of built attributes, interpersonal relationships, or safety. A subjective general construct known as “neighborhood disorder” aims to capture perceptions of both physical and social factors by incorporating dimensions such as safety, trust of neighbors, vandalism, and area cleanliness11; thus, this construct may include neighborhood characteristics that are particularly salient for the individual. Greater neighborhood disorder has been associated with higher levels of obesity indicators such as waist-to-hip ratio11 and BMI.12Despite the fact that both area-level objective and individual-level perceived aspects of neighborhoods demonstrate associations with obesity risk, the independence of these associations is unknown. Furthermore, their relevance to older populations and their gender-specific nature have not been established. Evidence also suggests that effects on obesity indicators may differ. For instance, objective neighborhood deprivation has been associated with higher BMI,10 whereas subjective neighborhood disorder has been associated with both higher BMI12 and higher central adiposity.11It would be useful to examine effects of neighborhood measures on separate indicators of obesity to understand which aspects are most strongly associated with obesity risk and, thus, the areas in which efforts to intervene would be best directed. In this study, involving a large sample of community-dwelling older adults in England, we sought to determine whether area-level objective neighborhood characteristics and individual-level subjective perceptions of the neighborhood environment are associated with obesity indicators independently of one another and whether these associations are gender-specific.     

Replacement-fed infants born to HIV-infected mothers in India have a high early postpartum rate of hospitalization

Access to safe breast-feeding alternatives for HIV-infected mothers and their infants in many settings is limited. We compared the rates of early postpartum hospitalization of infants born to HIV-infected mothers using different infant-feeding practices in a large government hospital in Pune, India. From March 1, 2000 to November 30, 2001, infants born to HIV-infected mothers were followed in a postpartum clinic. All mothers had received a standard short course of antenatal zidovudine. Infant-feeding practices were assessed within 3 d of delivery, prior to postpartum hospital discharge. Sixty-two of 148 mothers (42%) were breast-feeding their infants. Eighty-six of the mothers (58%) were providing replacement feeding, primarily diluted cow, goat or buffalo milk (top feeding). Twenty-one of the 148 participating infants (14.2%) born during the study period required hospitalization within the 1st 6 mo of life and 6 infants required repeat hospitalization. All hospitalized infants were receiving replacement feeding with a rate of 0.093 hospitalizations per 100 person-days (95% CI, 0.062 to 0.136). The reasons for hospitalization included acute gastroenteritis (48.1%), pneumonia (18.5%), septicemia (11.1%) and jaundice (11.1%). A high risk for early postpartum hospitalization was seen in replacement-fed infants born to HIV-infected mothers in Pune, India. In settings such as India, where access to safe replacement feeding is limited, interventions making exclusive breast-feeding safer for HIV-infected mothers and infants are needed. Such interventions would be valuable additions to the very effective national prevention programs that currently rely on the provision of short-course zidovudine and nevirapine.     

Effect of dietary n-3 and n-6 oils with and without food restriction on activity of antioxidant enzymes and lipid peroxidation in livers of cyclophosphamide treated autoimmune-prone NZB/W female mice

OBJECTIVE: Cyclophosphamide (CTX), an alkylating agent, is extensively used in the treatment of lupus nephritis, but its administration has been associated with free radical mediated oxidative stress. The present study was designed to investigate the effect of dietary corn oil (CO), fish oil (FO) and food restriction (FR) on the activities of hepatic antioxidant enzymes, fatty acid composition and lipid peroxidation following CTX administration in autoimmune-prone NZB/W female mice. METHODS: Autoimmune-prone NZB/W female mice were fed either ad libitum (AL) or food restricted (60% of AL intake), semipurified diets containing 5% CO or 5% FO supplemented with equal levels of antioxidants and injected with either phosphate buffered saline (PBS), or CTX (50 mg/kg body weight) every 10 days. Proteinuria was measured biweekly. The treatment was stopped at 10 months and diets were continued until the mice were killed at 12 months. Fatty acid composition, activity of antioxidant enzymes and lipid peroxidation were analyzed in liver homogenates, and anti-DNA antibodies were analyzed in the serum. RESULTS: Mice in the FO/AL dietary group exhibited significantly higher liver catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities compared to the CO/AL dietary group. CTX significantly decreased SOD and GSH-Px activity in the FO/AL group and CAT and GSH-Px in the CO/AL group. In AL fed mice given CTX, activities of CAT, GSH-Px and GST were significantly higher in mice fed FO diets than in mice fed CO diets. FR increased the activity of enzymes in both the CO and FO diet groups. In FR mice, CTX decreased CAT and GSH-Px activity in both the CO and FO dietary groups, but glutathione S-transferase (GST) only in the CO group. The decrease in SOD activity was not significant in either of the restricted groups. CTX significantly increased generation of thiobarbituric acid reactive substances (TBARS) in both AL groups. FR significantly decreased lipid peroxidation in both the CO and FO groups, with or without CTX. CTX decreased serum anti-DNA antibody levels in both the CO and FO dietary groups. FR also decreased antibody titer in both the CO and FO dietary groups, and it was decreased further with CTX treatment. FO fed animals had higher levels of n-3 fatty acids, whereas CO fed animals had high levels of n-6 fatty acids. CTX significantly increased 20:4 and decreased 18:1 in CO/AL fed animals, whereas it increased 18:1 and decreased 22:6 in FO/AL fed animals. CONCLUSIONS: Results obtained in the present study suggests that FO and, more significantly, FO combined with FR can have a beneficial effect in hepatic tissues subjected to CTX induced oxidative stress by regulating the activity of antioxidant enzymes. In addition, the study also indicates that n-3 and n-6 dietary lipids are susceptible to lipid peroxidation, particularly in the presence of a prooxidant like CTX, and that FR is beneficial in decreasing lipid peroxidation. The study also suggests that FO and CTX can have additive effects in preventing kidney disease in NZB/W mice.