Evaluating the effect of maternal non-communicable disease on adverse pregnancy outcomes and birthweight in Pakistan, a facility based retrospective cohort study.

Non-communicable diseases (NCDs) claim 74% of global lives, disproportionately affecting lower and middle-income countries like Pakistan. NCDs may increase the risk of preterm birth (PTB), caesarean section (CS), and low birthweight. This study aims to determine whether the high prevalence of NCDs in Pakistan play a role in the high rates of preterm births, and CS. This retrospective cohort study from Aga Khan University Hospital, Pakistan, investigated effects of pre-existing NCDs on pregnancy outcomes of 817 pregnant women. Medical records were used to generate odds ratios for the risk of PTB, labour outcome and birthweight in women with type 1 and type 2 diabetes, hypertension, asthma and thyroid disorders. Multinomial logistic regression and general linear models were used to adjust for confounding variables using IBM SPSS Statistics (v27). Type 2 diabetes significantly increased the risk of PTB and elective CS (both P < 0.05). Elective CS was significantly increased by hypertension and asthma (both, P < 0.05). Surprisingly, asthma halved the risk of PTB (P < 0.05), while type 1 diabetes significantly increased birthweight from 2832 to 3253g (P < 0.001). In conclusion, pre-existing NCDs increase the risk of negative pregnancy outcomes, including PTB, elective CS and birthweight. Asthma, however reduced PTB and justifies further investigation.

The impact of maternal obesity on in vivo uterine contractile activity during parturition in the rat.

Maternal obesity is associated with increased risk of prolonged and dysfunctional labor and emergency caesarean section. To elucidate the mechanisms behind the associated uterine dystocia, a translational animal model is required. Our previous work identified that exposure to a high-fat, high-cholesterol (HFHC) diet to induce obesity down-regulates uterine contractile associated protein expression and causes asynchronous contractions ex vivo. This study aims to investigate the impact of maternal obesity on uterine contractile function in vivo using intrauterine telemetry surgery. Virgin female Wistar rats were fed either a control (CON, n = 6) or HFHC (n = 6) diet for 6 weeks prior to conception, and throughout pregnancy. On Day 9 of gestation, a pressure-sensitive catheter was surgically implanted aseptically within the gravid uterus. Following 5 days recovery, intrauterine pressure (IUP) was recorded continuously until delivery of the 5th pup (Day 22). HFHC induced obesity led to a significant 1.5-fold increase in IUP (p = 0.026) and fivefold increase in frequency of contractions (p = 0.013) relative to CON. Determination of the time of labor onset identified that HFHC rats IUP (p = 0.046) increased significantly 8 h prior to 5th pup delivery, which contrasts to CON with no significant increase. Myometrial contractile frequency in HFHC rats significantly increased 12 h prior to delivery of the 5th pup (p = 0.023) compared to only 3 h in CON, providing evidence that labor in HFHC rats was prolonged by 9 h. In conclusion, we have established a translational rat model that will allow us to unravel the mechanism behind uterine dystocia associated with maternal obesity.

Acute changes to breast milk composition following consumption of high-fat and high-sugar meals.

Breast milk composition is influenced by habitual diet, yet little is known about the short-term effects of changes in maternal diet on breast milk macronutrient concentrations. Our aim was to determine the acute effect of increased consumption of sugar/fat on breast milk protein, lactose and lipids. Exclusively breastfeeding women (n = 9) were provided with a control, higher fat (+28 g fat) and higher sugar (+66 g sugar) diet over three separate days at least 1 week apart. Hourly breast milk samples were collected concurrently for the analysis of triglycerides, cholesterol, protein, and lactose concentrations. Breast milk triglycerides increased significantly following both the higher fat and sugar diet with a greater response to the higher sugar compared to control diet (mean differences of 3.05 g/dL ± 0.39 and 13.8 g/dL ± 0.39 in higher fat and sugar diets, respectively [P < 0.001]). Breast milk cholesterol concentrations increased most in response to the higher sugar diet (0.07 g/dL ± 0.005) compared to the control (0.04 g/dL) and the higher fat diet (0.05 g/dL) P < 0.005. Breast milk triglyceride and lactose concentrations increased (P < 0.001, P = 0.006), whereas protein decreased (p = 0.05) in response to the higher fat diet compared to the control. Independent of diet, there were significant variations in breast milk composition over the day; triglycerides and cholesterol concentrations were higher at end of day (P < 0.001), whereas protein and lactose concentrations peaked at Hour 10 (of 12) (P < 0.001). In conclusion, controlled short-term feeding to increase daily sugar/fat consumption altered breast milk triglycerides, cholesterol, protein and lactose. The variations observed in breast milk protein and lactose across the 12 h period is suggestive of a circadian rhythm.

Omega-6:Omega-3 Fatty Acid Ratio and Total Fat Content of the Maternal Diet Alter Offspring Growth and Fat Deposition in the Rat.

Omega-3 long-chain polyunsaturated fatty acids (LCPUFA) have been shown to inhibit lipogenesis and adipogenesis in adult rats. Their possible early life effects on offspring fat deposition, however, remain to be established. To investigate this, female Wistar rats (n = 6-9 per group) were fed either a 9:1 ratio of linoleic acid (LA) to alpha-linolenic acid (ALA) or a lower 1:1.5 ratio during pregnancy and lactation. Each ratio was fed at two total fat levels (18% vs. 36% fat w/w) and offspring were weaned onto standard laboratory chow. Offspring exposed to a 36% fat diet, irrespective of maternal dietary LA:ALA ratio, were lighter (male, 27 g lighter; female 19 g lighter; p < 0.0001) than those exposed to an 18% fat diet between 3 and 8 weeks of age. Offspring exposed to a low LA (18% fat) diet had higher proportions of circulating omega-3 LCPUFA and increased gonadal fat mass at 4 weeks of age (p < 0.05). Reduced Srebf1 mRNA expression of hepatic (p < 0.01), gonadal fat (p < 0.05) and retroperitoneal fat (p < 0.05) tissue was observed at 4 weeks of age in male and female offspring exposed to a 36% fat diet, and hepatic Srebf1 mRNA was also reduced in male offspring at 8 weeks of age (p < 0.05). Thus, while offspring fat deposition appeared to be sensitive to both maternal dietary LA:ALA ratio and total fat content, offspring growth and lipogenic capacity of tissues appeared to be more sensitive to maternal dietary fat content.

The effect of maternal dietary fat content and n-6:n-3 ratio on offspring growth and hepatic gene expression in the rat.

n-6 Fatty acids have been shown to exert pro-adipogenic effects, whereas n-3 fatty acids work in opposition. Increasing intakes of linoleic acid (LA; n-6) v. α-linolenic acid (ALA; n-3) in Western diets has led to the hypothesis that consumption of this diet during pregnancy may be contributing to adverse offspring health. This study investigated the effects of feeding a maternal dietary LA:ALA ratio similar to that of the Western diet (9:1) compared with a proposed 'ideal' ratio (about 1:1·5), at two total fat levels (18 v. 36 % fat, w/w), on growth and lipogenic gene expression in the offspring. Female Wistar rats were assigned to one of the four experimental groups throughout gestation and lactation. Offspring were culled at 1 and 2 weeks of age for sample collection. Offspring of dams consuming a 36 % fat diet were approximately 20 % lighter than those exposed to an 18 % fat diet (P < 0·001). Male, but not female, liver weight at 1 week was approximately 13 % heavier and had increased glycogen (P < 0·05), in offspring exposed to high LA (P < 0·01). Hepatic expression of lipogenic genes suggested an increase in lipogenesis in male offspring exposed to a 36 % fat maternal diet and in female offspring exposed to a low-LA diet, via increases in the expression of fatty acid synthase and sterol regulatory element-binding protein. Sexually dimorphic responses to altered maternal diet appeared to persist until 2 weeks of age. In conclusion, whilst maternal total fat content predominantly affected offspring growth, fatty acid ratio and total fat content had sexually dimorphic effects on offspring liver weight and composition.

Expression of cholesterol packaging and transport genes in human and rat placenta: impact of obesity and a high-fat diet.

Evidence suggests that sub-optimal maternal nutrition has implications for the developing offspring. We have previously shown that exposure to a low-protein diet during gestation was associated with upregulation of genes associated with cholesterol transport and packaging within the placenta. This study aimed to elucidate the effect of altering maternal dietary linoleic acid (LA; omega-6) to alpha-linolenic acid (ALA; omega-6) ratios as well as total fat content on placental expression of genes associated with cholesterol transport. The potential for maternal body mass index (BMI) to be associated with expression of these genes in human placental samples was also evaluated. Placentas were collected from 24 Wistar rats at 20-day gestation (term = 21-22-day gestation) that had been fed one of four diets containing varying fatty acid compositions during pregnancy, and from 62 women at the time of delivery. Expression of 14 placental genes associated with cholesterol packaging and transfer was assessed in rodent and human samples by quantitative real time polymerase chain reaction. In rats, placental mRNA expression of ApoA2, ApoC2, Cubn, Fgg, Mttp and Ttr was significantly elevated (3-30 fold) in animals fed a high LA (36% fat) diet, suggesting increased cholesterol transport across the placenta in this group. In women, maternal BMI was associated with fewer inconsistent alterations in gene expression. In summary, sub-optimal maternal nutrition is associated with alterations in the expression of genes associated with cholesterol transport in a rat model. This may contribute to altered fetal development and potentially programme disease risk in later life. Further investigation of human placenta in response to specific dietary interventions is required.

The impact of exposure to cafeteria diet during pregnancy or lactation on offspring growth and adiposity before weaning.

Exposure to maternal obesity during early-life can have adverse consequences for offspring growth and adiposity. We aimed to assess the relative contributions of exposure to maternal obesity, induced by a highly varied cafeteria diet, during pregnancy and lactation on these measures in rat offspring prior to weaning. Female Wistar rats were fed either a control (C) or cafeteria diet (O) for 8 weeks before mating, throughout pregnancy and lactation. Offspring were cross-fostered at birth to a dam on the same (CC,OO) or alternate diet prior to birth (CO,OC). Feeding a cafeteria diet based on 40 different foods, was associated with a sustained period of elevated energy intake before birth and during lactation (up to 1.7-fold), through increased sugar, total fat and saturated fat intake, and lower protein consumption. Cafeteria fed dams sustained greater weight than animals fed a control chow diet and greater perirenal adiposity by the end of lactation. Exposure to obesity during pregnancy was associated with lower offspring birth weight and body weight in early-postnatal life. In contrast, exposure during lactation alone reduced offspring weight but increased adiposity in male CO offspring before weaning. This research highlights that exposure to maternal obesity during lactation alone can programme adiposity in a sex specific manner.

Identification of Fatty Acid Binding Protein 5 Inhibitors Through Similarity-Based Screening.

Fatty acid binding protein 5 (FABP5) is a promising target for development of inhibitors to help control pain and inflammation. In this work, computer-based docking (DOCK6 program) was employed to screen ∼2 M commercially available compounds to FABP5 based on an X-ray structure complexed with the small molecule inhibitor SBFI-26 previously identified by our group (also through virtual screening). The goal was discovery of additional chemotypes. The screen resulted in the purchase of 78 candidates, which led to the identification of a new inhibitor scaffold (STK-0) with micromolar affinity and apparent selectivity for FABP5 over FABP3. A second similarity-based screen resulted in three additional hits (STK-15, STK-21, STK-22) from which preliminary SAR could be derived. Notably, STK-15 showed comparable activity to the SBFI-26 reference under the same assay conditions (1.40 vs 0.86 µM). Additional molecular dynamics simulations, free energy calculations, and structural analysis (starting from DOCK-generated poses) revealed that R enantiomers (dihydropyrrole scaffold) of STK-15 and STK-22 have a more optimal composition of functional groups to facilitate additional H-bonds with Arg109 of FABP5. This observation suggests enantiomerically pure compounds could show enhanced activity. Overall, our study highlights the utility of using similarity-based screening methods to discover new inhibitor chemotypes, and the identified FABP5 hits provide a strong starting point for future efforts geared to improve activity.

Exposure to maternal obesity during suckling outweighs in utero exposure in programming for post-weaning adiposity and insulin resistance in rats.

Exposure to maternal obesity during early development programmes adverse metabolic health in rodent offspring. We assessed the relative contributions of obesity during pregnancy and suckling on metabolic health post-weaning. Wistar rat offspring exposed to control (C) or cafeteria diet (O) during pregnancy were cross-fostered to dams on the same (CC, OO) or alternate diet during suckling (CO, OC) and weaned onto standard chow. Measures of offspring metabolic health included growth, adipose tissue mass, and 12-week glucose and insulin concentrations during an intraperitoneal glucose tolerance test (ipGTT). Exposure to maternal obesity during lactation was a driver for reduced offspring weight post-weaning, higher fasting blood glucose concentrations and greater gonadal adiposity (in females). Males displayed insulin resistance, through slower glucose clearance despite normal circulating insulin and lower mRNA expression of PIK3R1 and PIK3CB in gonadal fat and liver respectively. In contrast, maternal obesity during pregnancy up-regulated the insulin signalling genes IRS2, PIK3CB and SREBP1-c in skeletal muscle and perirenal fat, favouring insulin sensitivity. In conclusion exposure to maternal obesity during lactation programmes offspring adiposity and insulin resistance, overriding exposure to an optimal nutritional environment in utero, which cannot be alleviated by a nutritionally balanced post-weaning diet.

Incarvillateine produces antinociceptive and motor suppressive effects via adenosine receptor activation.

(-)-Incarvillateine (INCA) is a natural product that has garnered attention due to its purported analgesic effects and historical use as a pain reliever in China. α-Truxillic acid monoesters (TAMEs) constitute a class of inhibitors targeting fatty acid binding protein 5 (FABP5), whose inhibition produces analgesia in animal models. The structural similarity between INCA and TAMEs motivated us to assess whether INCA exerts its antinociceptive effects via FABP inhibition. We found that, in contrast to TAMEs, INCA did not exhibit meaningful binding affinities toward four human FABP isoforms (FABP3, FABP4, FABP5 and FABP7) in vitro. INCA-TAME, a putative monoester metabolite of INCA that closely resembles TAMEs also lacked affinity for FABPs. Administration of INCA to mice produced potent antinociceptive effects while INCA-TAME was without effect. Surprisingly, INCA also potently suppressed locomotor activity at the same dose that produces antinociception. The motor suppressive effects of INCA were reversed by the adenosine A2 receptor antagonist 3,7-dimethyl-1-propargylxanthine. Collectively, our results indicate that INCA and INCA-TAME do not inhibit FABPs and that INCA exerts potent antinociceptive and motor suppressive effects at equivalent doses. Therefore, the observed antinociceptive effects of INCA should be interpreted with caution.

FABP1 controls hepatic transport and biotransformation of Δ9-THC.

The increasing use of medical marijuana highlights the importance of developing a better understanding of cannabinoid metabolism. Phytocannabinoids, including ∆9-tetrahydrocannabinol (THC), are metabolized and inactivated by cytochrome P450 enzymes primarily within the liver. The lipophilic nature of cannabinoids necessitates mechanism(s) to facilitate their intracellular transport to metabolic enzymes. Here, we test the central hypothesis that liver-type fatty acid binding protein (FABP1) mediates phytocannabinoid transport and subsequent inactivation. Using X-ray crystallography, molecular modeling, and in vitro binding approaches we demonstrate that FABP1 accommodates one molecule of THC within its ligand binding pocket. Consistent with its role as a THC carrier, biotransformation of THC was reduced in primary hepatocytes obtained from FABP1-knockout (FABP1-KO) mice. Compared to their wild-type littermates, administration of THC to male and female FABP1-KO mice potentiated the physiological and behavioral effects of THC. The stark pharmacodynamic differences were confirmed upon pharmacokinetic analyses which revealed that FABP1-KO mice exhibit reduced rates of THC biotransformation. Collectively, these data position FABP1 as a hepatic THC transport protein and a critical mediator of cannabinoid inactivation. Since commonly used medications bind to FABP1 with comparable affinities to THC, our results further suggest that FABP1 could serve a previously unrecognized site of drug-drug interactions.

Maternal dietary ratio of linoleic acid to alpha-linolenic acid during pregnancy has sex-specific effects on placental and fetal weights in the rat.

BACKGROUND: Increased consumption of linoleic acid (LA, omega-6) in Western diets coupled with the pro-inflammatory and adipogenic properties of its derivatives has led to suggestions that fetal exposure to this dietary pattern could be contributing to the intergenerational cycle of obesity. METHOD: This study aimed to evaluate the effects of maternal consumption of a LA to alpha-linolenic acid (ALA) ratio similar to modern Western diets (9:1) compared to a lower ratio (1:1.5) on placental and fetal growth, and to determine any cumulative effects by feeding both diets at two total fat levels (18% vs 36% fat w/w). Female Wistar rats (n = 5-7/group) were assigned to one of the four experimental diets prior to mating until 20d of gestation. RESULTS: Fatty acid profiles of maternal and fetal blood and placental tissue at 20d gestation were different between dietary groups, and largely reflected dietary fatty acid composition. Female fetuses were heavier (2.98 ± 0.06 g vs 3.36 ± 0.07 g, P < 0.01) and male placental weight was increased (0.51 ± 0.02 g vs 0.58 ± 0.02 g, P < 0.05) in the low LA:ALA groups. Female fetuses of dams exposed to a 36% fat diet had a reduced relative liver weight irrespective of LA:ALA ratio (7.61 ± 0.22% vs 6.93 ± 0.19%, P < 0.05). These effects occurred in the absence of any effect of the dietary treatments on maternal bodyweight, fat deposition or expression of key lipogenic genes in maternal and fetal liver or maternal adipose tissue. CONCLUSION: These findings suggest that both the total fat content as well as the LA:ALA ratio of the maternal diet have sex-specific implications for the growth of the developing fetus.

Author Correction: Maternal obesity-induced decreases in plasma, hepatic and uterine polyunsaturated fatty acids during labour is reversed through improved nutrition at conception.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

SAR studies on truxillic acid mono esters as a new class of antinociceptive agents targeting fatty acid binding proteins.

Fatty acid binding proteins (FABPs) serve as critical modulators of endocannabinoid signaling by facilitating the intracellular transport of anandamide and whose inhibition potentiates anandamide signaling. Our previous work has identified a novel small-molecule FABP inhibitor, α-truxillic acid 1-naphthyl monoester (SB-FI-26, 3) that has shown efficacy as an antinociceptive and anti-inflammatory agent in rodent models. In the present work, we have performed an extensive SAR study on a series of 3-analogs as novel FABP inhibitors based on computer-aided inhibitor drug design and docking analysis, chemical synthesis and biological evaluations. The prediction of binding affinity of these analogs to target FABP3, 5 and 7 isoforms was performed using the AutoDock 4.2 program, using the recently determined co-crystal structures of 3 with FABP5 and FABP7. The compounds with high docking scores were synthesized and evaluated for their activities using a fluorescence displacement assay against FABP3, 5 and 7. During lead optimization, compound 3l emerged as a promising compound with the Ki value of 0.21 µM for FABP 5, 4-fold more potent than 3 (Ki, 0.81 µM). Nine compounds exhibit similar or better binding affinity than 3, including compounds 4b (Ki, 0.55 µM) and 4e (Ki, 0.68 µM). Twelve compounds are selective for FABP5 and 7 with >10 µM Ki values for FABP3, indicating a safe profile to avoid potential cardiotoxicity concerns. Compounds 4f, 4j and 4k showed excellent selectivity for FABP5 and would serve as other new lead compounds. Compound 3a possessed high affinity and high selectivity for FABP7. Compounds with moderate to high affinity for FABP5 displayed antinociceptive effects in mice while compounds with low FABP5 affinity lacked in vivo efficacy. In vivo pain model studies in mice revealed that exceeding hydrophobicity significantly affects the efficacy. Thus, among the compounds with high affinity to FABP5 in vitro, the compounds with moderate hydrophobicity were identified as promising new lead compounds for the next round of optimization, including compounds 4b and 4j. For select cases, computational analysis of the observed SAR, especially the selectivity of new inhibitors to particular FABP isoforms, by comparing docking poses, interaction map, and docking energy scores has provided useful insights.

Lipocalin-Type Prostaglandin D Synthase Is a Novel Phytocannabinoid-Binding Protein.

Lipocalin-type prostaglandin D synthase (L-PGDS; EC:5.3.99.2) is an enzyme with dual functional roles as a prostaglandin D2 -synthesizing enzyme and as an extracellular transporter for diverse lipophilic compounds in the cerebrospinal fluid (CSF). Transport of hydrophobic endocannabinoids is mediated by serum albumin in the blood and intracellularly by the fatty acid binding proteins, but no analogous transport mechanism has yet been described in CSF. L-PGDS has been reported to promiscuously bind a wide variety of lipophilic ligands and is among the most abundant proteins found in the CSF. Here, we examine the binding of several classes of endogenous and synthetic ligands to L-PGDS. Endocannabinoids exhibited low affinity toward L-PGDS, while cannabinoid metabolites and synthetic cannabinoids displayed higher affinities for L-PGDS. These results indicate that L-PGDS is unlikely to function as a carrier for endocannabinoids in the CSF, but it may bind and transport a subset of cannabinoids.

Fatty-acid-binding protein 5 controls retrograde endocannabinoid signaling at central glutamate synapses.

Endocannabinoids (eCBs) are lipid-signaling molecules involved in the regulation of numerous behaviors and physiological functions. Released by postsynaptic neurons, eCBs mediate retrograde modulation of synaptic transmission and plasticity by activating presynaptic cannabinoid receptors. While the cellular mechanisms by which eCBs control synaptic function have been well characterized, the mechanisms controlling their retrograde synaptic transport remain unknown. Here, we demonstrate that fatty-acid-binding protein 5 (FABP5), a canonical intracellular carrier of eCBs, is indispensable for retrograde eCB transport in the dorsal raphe nucleus (DRn). Thus, pharmacological inhibition or genetic deletion of FABP5 abolishes both phasic and tonic eCB-mediated control of excitatory synaptic transmission in the DRn. The blockade of retrograde eCB signaling induced by FABP5 inhibition is not mediated by impaired cannabinoid receptor function or reduced eCB synthesis. These findings indicate that FABP5 is essential for retrograde eCB signaling and may serve as a synaptic carrier of eCBs at central synapses.

Fatty acid-binding protein 5 controls microsomal prostaglandin E synthase 1 (mPGES-1) induction during inflammation.

Fatty acid-binding proteins (FABPs) are intracellular lipid carriers that regulate inflammation, and pharmacological inhibition of FABP5 reduces inflammation and pain. The mechanism(s) underlying the anti-inflammatory effects associated with FABP5 inhibition is poorly understood. Herein, we identify a novel mechanism through which FABP5 modulates inflammation. In mice, intraplantar injection of carrageenan induces acute inflammation that is accompanied by edema, enhanced pain sensitivity, and elevations in proinflammatory cytokines and prostaglandin E2 (PGE2). Inhibition of FABP5 reduced pain, edema, cytokine, and PGE2 levels. PGE2 is a major eicosanoid that enhances pain in the setting of inflammation, and we focused on the mechanism(s) through which FABP5 modulates PGE2 production. Cyclooxygenase 2 (COX-2) and microsomal prostaglandin E synthase 1 (mPGES-1) are enzymes up-regulated at the site of inflammation and account for the bulk of PGE2 biosynthesis. Pharmacological or genetic FABP5 inhibition suppressed the induction of mPGES-1 but not COX-2 in carrageenan-injected paws, which occurred predominantly in macrophages. The cytokine interleukin 1ß (IL-1ß) is a major inducer of mPGES-1 during inflammation. Using A549 cells that express FABP5, IL-1ß stimulation up-regulated mPGES-1 expression, and mPGES-1 induction was attenuated in A549 cells bearing a knockdown of FABP5. IL-1ß up-regulates mPGES-1 via NF-κB, which activates the mPGES-1 promoter. Knockdown of FABP5 reduced the activation and nuclear translocation of NF-κB and attenuated mPGES-1 promoter activity. Deletion of NF-κB-binding sites within the mPGES-1 promoter abrogated the ability of FABP5 to inhibit mPGES-1 promoter activation. Collectively, these results position FABP5 as a novel regulator of mPGES-1 induction and PGE2 biosynthesis during inflammation.

Maternal obesity-induced decreases in plasma, hepatic and uterine polyunsaturated fatty acids during labour is reversed through improved nutrition at conception.

Maternal obesity is associated with prolonged and dysfunctional labour, potentially through decreased synthesis of prostaglandins that stimulate myometrial contractions. We assessed the impact of maternal obesity on concentrations of precursor fatty acids (FA) for prostaglandin synthesis and whether any changes could be reversed by improved nutrition post-conception. Wistar rats were fed control (CON) or High-Fat, High-cholesterol (HFHC) diets 6 weeks before mating. At conception half the dams switched diets providing 4 dietary groups: (1) CON, (2) HFHC, (3) CON-HFHC or (4) HFHC-CON. During parturition rats were euthanized and FA composition of plasma, liver and uterus determined. Visceral fat was doubled in rats exposed to the HFHC diet prior to and/or during pregnancy compared to CON. HFHC diet increased MUFAs but decreased omega-3 and omega-6 PUFAs in plasma and liver. Uterine omega-3 FA concentrations were halved in HFHC versus CON rats, but all other FAs were similar. Switching from HFHC to CON diet at conception restored all FA profiles to those seen in CON rats. The increased MUFA and decreased PUFA concentrations in obese HFHC dams may contribute to aberrant prostaglandin synthesis and dysfunctional myometrial activity and it may be possible to reverse these changes, and potentially improve labour outcomes, by improving nutrition at conception.

The Antinociceptive Agent SBFI-26 Binds to Anandamide Transporters FABP5 and FABP7 at Two Different Sites.

Human FABP5 and FABP7 are intracellular endocannabinoid transporters. SBFI-26 is an α-truxillic acid 1-naphthyl monoester that competitively inhibits the activities of FABP5 and FABP7 and produces antinociceptive and anti-inflammatory effects in mice. The synthesis of SBFI-26 yields several stereoisomers, and it is not known how the inhibitor binds the transporters. Here we report co-crystal structures of SBFI-26 in complex with human FABP5 and FABP7 at 2.2 and 1.9 Å resolution, respectively. We found that only (S)-SBFI-26 was present in the crystal structures. The inhibitor largely mimics the fatty acid binding pattern, but it also has several unique interactions. Notably, the FABP7 complex corroborates key aspects of the ligand binding pose at the canonical site previously predicted by virtual screening. In FABP5, SBFI-26 was unexpectedly found to bind at the substrate entry portal region in addition to binding at the canonical ligand-binding pocket. Our structural and binding energy analyses indicate that both R and S forms appear to bind the transporter equally well. We suggest that the S enantiomer observed in the crystal structures may be a result of the crystallization process selectively incorporating the (S)-SBFI-26-FABP complexes into the growing lattice, or that the S enantiomer may bind to the portal site more rapidly than to the canonical site, leading to an increased local concentration of the S enantiomer for binding to the canonical site. Our work reveals two binding poses of SBFI-26 in its target transporters. This knowledge will guide the development of more potent FABP inhibitors based upon the SBFI-26 scaffold.

Fatty-acid-binding protein inhibition produces analgesic effects through peripheral and central mechanisms.

Background Fatty-acid-binding proteins (FABPs) are intracellular carriers for endocannabinoids, N-acylethanolamines, and related lipids. Previous work indicates that systemically administered FABP5 inhibitors produce analgesia in models of inflammatory pain. It is currently not known whether FABP inhibitors exert their effects through peripheral or central mechanisms. Here, we examined FABP5 distribution in dorsal root ganglia and spinal cord and examined the analgesic effects of peripherally and centrally administered FABP5 inhibitors. Results Immunofluorescence revealed robust expression of FABP5 in lumbar dorsal root ganglia. FABP5 was distributed in peptidergic calcitonin gene-related peptide-expressing dorsal root ganglia and non-peptidergic isolectin B4-expressing dorsal root ganglia. In addition, the majority of dorsal root ganglia expressing FABP5 also expressed transient receptor potential vanilloid 1 (TRPV1) and peripherin, a marker of nociceptive fibers. Intraplantar administration of FABP5 inhibitors reduced thermal and mechanical hyperalgesia in the complete Freund's adjuvant model of chronic inflammatory pain. In contrast to its robust expression in dorsal root ganglia, FABP5 was sparsely distributed in the lumbar spinal cord and intrathecal administration of FABP inhibitor did not confer analgesic effects. Administration of FABP inhibitor via the intracerebroventricular (i.c.v.) route reduced thermal hyperalgesia. Antagonists of peroxisome proliferator-activated receptor alpha blocked the analgesic effects of peripherally and i.c.v. administered FABP inhibitor while antagonism of cannabinoid receptor 1 blocked the effects of peripheral FABP inhibition and a TRPV1 antagonist blocked the effects of i.c.v. administered inhibitor. Although FABP5 and TRPV1 were co-expressed in the periaqueductal gray region of the brain, which is known to modulate pain, knockdown of FABP5 in the periaqueductal gray using adeno-associated viruses and pharmacological FABP5 inhibition did not produce analgesic effects. Conclusions This study demonstrates that FABP5 is highly expressed in nociceptive dorsal root ganglia neurons and FABP inhibitors exert peripheral and supraspinal analgesic effects. This indicates that peripherally restricted FABP inhibitors may serve as a new class of analgesic and anti-inflammatory agents.