Cardiovascular and renal profiles in rat offspring that do not undergo catch-up growth after exposure to maternal protein restriction.

Maternal protein restriction is often associated with structural and functional sequelae in offspring, particularly affecting growth and renal-cardiovascular function. However, there is little understanding as to whether hypertension and kidney disease occur because of a primary nephron deficit or whether controlling postnatal growth can result in normal renal-cardiovascular phenotypes. To investigate this, female Sprague-Dawley rats were fed either a low-protein (LP, 8.4% protein) or normal-protein (NP, 19.4% protein) diet prior to mating and until offspring were weaned at postnatal day (PN) 21. Offspring were then fed a non 'growth' (4.6% fat) which ensured that catch-up growth did not occur. Offspring growth was determined by weight and dual energy X-ray absorptiometry. Nephron number was determined at PN21 using the disector-fractionator method. Kidney function was measured at PN180 and PN360 using clearance methods. Blood pressure was measured at PN360 using radio-telemetry. Body weight was similar at PN1, but by PN21 LP offspring were 39% smaller than controls (Pdiet < 0.001). This difference was due to proportional changes in lean muscle, fat, and bone content. LP offspring remained smaller than NP offspring until PN360. In LP offspring, nephron number was 26% less in males and 17% less in females, than NP controls (Pdiet < 0.0004). Kidney function was similar across dietary groups and sexes at PN180 and PN360. Blood pressure was similar in LP and NP offspring at PN360. These findings suggest that remaining on a slow growth trajectory after exposure to a suboptimal intrauterine environment does not lead to the development of kidney dysfunction and hypertension.

Analysis of structure and gene expression in developing kidneys of male and female rats exposed to low protein diets in utero.

A maternal low protein (LP) diet in rodents often results in low nephron endowment and renal pathophysiology in adult life, with outcomes often differing between male and female offspring. Precisely how a maternal LP diet results in low nephron endowment is unknown. We conducted morphological and molecular studies of branching morphogenesis and nephrogenesis to identify mechanisms and timepoints that might give rise to low nephron endowment. Sprague-Dawley rats were fed a normal protein (19.4% protein, NP) or LP (9% protein) diet for 3 weeks prior to mating and throughout gestation. Embryonic day 14.25 (E14.25) kidneys from males and females were either cultured for 2 days after which branching morphogenesis was quantified, or frozen for gene expression analysis. Real-time PCR was used to quantify expression of key nephrogenesis and branching morphogenesis genes at E14.25 and 17.25. At E17.25, nephron number was determined in fixed tissue. There was no effect of either maternal diet or sex on branching morphogenesis. Nephron number at E17.25 was 14% lower in male and female LP offspring than in NP controls. At E14.25 expression levels of genes involved in branching morphogenesis (Gfrα1, Bmp4, Gdnf) and nephrogenesis (Hnf4a, Pax2, Wnt4) were similar in the dietary groups, but significant differences between sexes were identified. At E17.25, expression of Gfrα1, Gdnf, Bmp4, Pax2 and Six2 was lower in LP offspring than NP offspring, in both male and female offspring. These findings provide new insights into how a LP diet leads to low nephron endowment and renal sexual dimorphism.

Characterisation of a pucBA deletion mutant from Rhodopseudomonas palustris lacking all but the pucBAd genes.

Rhodopseudomonas palustris is a species of purple photosynthetic bacteria that has a multigene family of puc genes that encode the alpha and beta apoproteins, which form the LH2 complexes. A genetic dissection strategy has been adopted in order to try and understand which spectroscopic form of LH2 these different genes produce. This paper presents a characterisation of one of the deletion mutants generated in this program, the pucBAd only mutant. This mutant produces an unusual spectroscopic form of LH2 that only has a single large NIR absorption band at 800 nm. Spectroscopic and pigment analyses on this complex suggest that it has basically a similar overall structure as that of the wild-type HL LH2 complex. The mutant has the unique phenotype where the mutant LH2 complex is only produced when cells are grown at LL. At HL the mutant only produces the LH1-RC core complex.

Reversible DNA micro-patterning using the fluorous effect.

We describe a new method for the immobilisation of DNA into defined patterns with sub-micron resolution, using the fluorous effect. The method is fully reversible via a simple solvent wash, allowing the patterning, regeneration and re-patterning of surfaces with no degradation in binding efficiency following multiple removal/attachment cycles of different DNA sequences.

Validity and Representative Data of the MRCI With Legally Involved Juveniles.

Recognized for nearly four decades, most juvenile suspects waive their Miranda rights and almost immediately provide self-incriminating evidence. Miranda-specific measures were eventually developed to understand their capacities and limitations. With extensive revisions, the Miranda Rights Comprehension Instruments (MRCI) were normed and validated. Beyond reliability, the current study addresses the convergent and discriminant validity of the MRCI. In response to Frumkin and Sellbom's criticism of the MRCI's norms, the current research provides representative data on 245 legally involved juveniles with percentiles to facilitate the interpretation of MRCI data. The current investigation is also the first MRCI study to link directly Miranda comprehension (i.e., the knowing prong) to Miranda reasoning (i.e., the intelligent prong) of waiver decisions.

DNA-directed spatial assembly of photosynthetic light-harvesting proteins.

This manuscript describes the surface immobilization of a light-harvesting complex to prescribed locations directed by the sequence-selective recognition of duplex DNA. An engineered light-harvesting complex (RC-LH1) derived from Rhodopseudomonas (Rps.) palustris containing the zinc finger (ZF) domain zif268 was prepared. The zif268 domain directed the binding of zfRC-LH1 to target double-stranded DNA sequences both in solution and when immobilized on lithographically defined micro-patterns. Excitation energy transfer from the carotenoids to the bacteriochlorophyll pigments within zfRC-LH1 confirmed that the functional and structural integrity of the complex is retained after surface immobilization.

Maternal overnutrition programs changes in the expression of skeletal muscle genes that are associated with insulin resistance and defects of oxidative phosphorylation in adult male rat offspring.

Children of obese mothers have increased risk of metabolic syndrome as adults. Here we report the effects of a high-fat diet in the absence of maternal obesity at conception on skeletal muscle metabolic and transcriptional profiles of adult male offspring. Female Sprague Dawley rats were fed a diet rich in saturated fat and sucrose [high-fat diet (HFD): 23.5% total fat, 9.83% saturated fat, 20% sucrose wt:wt] or a normal control diet [(CD) 7% total fat, 0.5% saturated fat, 10% sucrose wt:wt] for the 3 wk prior to mating and throughout pregnancy and lactation. Maternal weights were not different at conception; however, HFD-fed dams were 22% heavier than controls during pregnancy. On a normal diet, the male offspring of HFD-fed dams were not heavier than controls but demonstrated features of insulin resistance, including elevated plasma insulin concentration [40.1 ± 2.5 (CD) vs 56.2 ± 6.1 (HFD) mU/L; P = 0.023]. Next-generation mRNA sequencing was used to identify differentially expressed genes in the offspring soleus muscle, and gene set enrichment analysis (GSEA) was used to detect coordinated changes that are characteristic of a biological function. GSEA identified 15 upregulated pathways, including cytokine signaling (P < 0.005), starch and sucrose metabolism (P < 0.017), inflammatory response (P < 0.024), and cytokine-cytokine receptor interaction (P < 0.037). A further 8 pathways were downregulated, including oxidative phosphorylation (P < 0.004), mitochondrial matrix (P < 0.006), and electron transport/uncoupling (P < 0.022). Phosphorylation of the insulin signaling protein kinase B was reduced [2.86 ± 0.63 (CD) vs 1.02 ± 0.27 (HFD); P = 0.027] and mitochondrial complexes I, II, and V protein were downregulated by 50-68% (P < 0.005). On a normal diet, the male offspring of HFD-fed dams did not become obese adults but developed insulin resistance, with transcriptional evidence of muscle cytokine activation, inflammation, and mitochondrial dysfunction. These data indicate that maternal overnutrition, even in the absence of prepregnancy obesity, can promote metabolic dysregulation and predispose offspring to type 2 diabetes.

White adipocytes: more than just fat depots.

Globally 30% of adults are overweight or obese. The white adipocyte is a major component of adipose tissue, and as the obesity epidemic increases it is critically important to understand the factors determining adipocyte development and function. Adipogenesis has two distinct phases; determination of the adipocyte from a multipotent stem cell, and terminal differentiation of a pre-adipocyte into a mature adipocyte. The environment encountered in early life can alter adipocyte number and size and potentially impact upon adipocyte endocrine function in adulthood. These alterations may contribute to the pathophysiology of chronic diseases and thus targeted therapy of the adipocyte has great potential for treating the current obesity epidemic.

Developmental origins of obesity-related hypertension.

1. In the past 30 years the prevalence of obesity and overweight have doubled. It is now estimated that globally over 500 million adults are obese and a further billion adults are overweight. Obesity is a cardiovascular risk factor and some studies suggest that up to 70% of cases of essential hypertension may be attributable, in part, to obesity. Increasingly, evidence supports a view that obesity-related hypertension may be driven by altered hypothalamic signalling, which results in inappropriately high appetite and sympathetic nerve activity to the kidney. 2. In addition to the adult risk factors for obesity and hypertension, the environment encountered in early life may 'programme' the development of obesity, hypertension and cardiovascular disease. In particular, maternal obesity or high dietary fat intake in pregnancy may induce changes in fetal growth trajectories and predispose individuals to develop obesity and related sequelae. 3. The mechanisms underlying the programming of obesity-related hypertension are becoming better understood. However, several issues require clarification, particularly with regard to the role of the placenta in transferring fatty acid to the fetal compartment, the impact of placental inflammation and cytokine production in obesity. 4. By understanding which factors are most associated with the development of obesity and hypertension in the offspring, we can focus therapeutic and behavioural interventions to most efficiently reduce the intergenerational propagation of the obesity cycle.