Monitoring and evaluation of childhood stunting reduction program based on fish supplement product in North Sumatera, Indonesia.

The government of Serdang Bedagai Regency initiated a supplementation program to reduce the high prevalence of stunting in the area by delivering extra supplementation, which were nutritious biscuits from national government and fish-based supplement produced from local resources. A 6-month study from April 2022 to September 2022 was conducted to monitor and evaluate the government program that involved 219 under-5-year-old children with height-for-age Z-score (HAZ-score) below - 2. We observed the stunting prevalence reduction by 37.00%, where 81 children recovered from stunting (HAZ-score ≥ - 2). Furthermore, the mean HAZ-score and WHZ-score (Weight-for-Height Z-score) were monitored to significantly improve by 0.97 ± 1.45 (P-value = 1.74e-14) and 1.00 ± 2.18 (P-value = and 2.40e-8), subsequently. The most significant improvement in HAZ-score was monitored among children receiving fish-based supplements with 1.04 ± 1.44 improvement (P-value = 6.59e-17). Then, a significant WHZ-score improvement was reported from children consuming fish-based supplements and a combination of fish-based supplements with nutritious biscuits (P-value = 2.32e-8 and 5.48e-5) by 1.04 ± 2.29 and 0.83 ± 1.84, respectively. The results of the observation become evidence that the program could effectively reduce the prevalence of stunting in children below five years old, especially among children who received locally produced fish-based supplements.

Knowledge, attitude, and practices of midwives on premature rupture of membranes (PROM): A cross-sectional study in Samosir and Toba, Indonesia.

Indonesia has a significantly higher maternal mortality ratio (MMR) than other countries in Southeast Asia, and infection is one of the most common causes of maternal deaths, of which premature rupture of membranes (PROM) can be the consequence of the infections. In primary healthcare settings, midwives play an important role in identifying and managing PROM appropriately; however, studies on their knowledge, attitudes, and practices related to PROM are limited. The aim of this study was to determine the midwives' knowledge, attitude and healthcare practice on PROM in Indonesia. A cross-sectional study was conducted among midwives at primary healthcare facilities in Samosir and Toba Regency, North Sumatra, Indonesia, from July to November 2022. The knowledge, attitude and practice towards PROM were assessed. Results showed that 57.5% of midwives had poor knowledge and 35.1% had poor attitude levels. There were 4.9% of midwives referred the patients immediately to the hospital. Our data indicated that aged 31-40 or 41-50 years, having a lower than bachelor degree and having a higher monthly number of referred PROM patients were significantly associated with poor knowledge compared to younger, having a bachelor degree, and lower monthly referral patient number, respectively. Similarly, younger, having higher degree and a having lower monthly referral number of PROM cases were associated with higher chances of having a sufficient-good attitude towards PROM. This study highlights that a significant percentage of midwives had poor levels of knowledge and attitude, and age, educational level and monthly referral number of PROM cases were associated with the level of knowledge and attitude.

Efficacy of metamizole to prevent kidney injury after renal-ischaemic reperfusion injury in Wistar rats.

Background: Renal ischaemia-reperfusion injury (RIRI) is a common kidney procedure complication due to temporary blood flow interruption, leading to kidney injuries. This study aimed to analyze the effect of metamizole on the levels of interleukin-18 (IL-18), neutrophil-gelatinase-associated lipocalin (NGAL), myeloperoxidase (MPO), and histopathological changes in rats with RIRI. Materials and methods: Animal pre-clinical design study was used. Thirty-two male Wistar rats (Rattus norvegicus) were divided into four groups: negative control, positive control, M100, and M200. Blood samples were collected by intracardiac puncture, followed by bilateral nephrectomy and analyzed histopathologically. Results: Significant difference in IL-18 levels between positive control vs negative control (114.1 + 12.07 vs. 94.0 + 11.4; P = 0.019) and positive control vs M100 (114.1 + 12.07 vs. 86.9 + 8.34; P = 0.007). There was no difference in NGAL. M100 group had the lowest serum MPO levels (14.78+2.01), there was a significant difference in MPO levels in all pairwise analyses. There was a difference in cumulative EGTI scores among the study groups [positive 10.5 (8-11) vs. negative 9 (7-10) vs. M100 9 (7-10) vs. M200 9 (7-11); P = 0.021]. Conclusion: Metamizole 100 mg/kgBW can reduce IL-18 and MPO levels in RIRI, giving more optimal results without affecting NGAL levels. Metamizole administration can reduce cumulative EGTI scores in RIRI, both at doses of 100 mg/kgBW and 200 mg/kgBW. This study shows that Metamizole can be used to prevent kidney injury caused by RIRI. IL-18 and MPO can be biomarkers in predicting kidney injury in RIRI.

SARS-CoV-2 lineages circulating during the first wave of the pandemic in North Sumatra, Indonesia.

Objectives: To determine the lineage distribution of the virus during the first wave of the pandemic in North Sumatra, Indonesia. Methods: A total of 20 samples with positive results based on reverse transcription-polymerase chain reaction were selected for virus culture and then performed whole-genome sequence analysis using next-generation sequencing which was applied by the Illumina MiSeq instrument. Results: Whole-genome sequence analysis revealed that the majority of our samples belong to lineages B.1.468 (n = 10), B.1 (n = 5), B.1.1 (n = 2), B.1.1.398 (n = 2), and B.6 (n = 1). Other unique amino acid mutations found in our samples were present in A58T on non-structural protein (NSP3) (70%), P323L on NSP12 (95%), Q57H on NS3 protein (75%), and D614G on S (100%). Conclusion: The SARS-CoV-2 lineage B.1.468 may be the main virus variant circulating in North Sumatra at the beginning of the emergence of COVID-19 cases in this province.

Use of saliva as an alternative diagnostic method for diagnosis of COVID-19.

Background: Mass population testing has been recommended to contain the spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. However, the use of nasopharyngeal swab specimens has caused many logistic challenges. This study investigated the sensitivity and specificity of saliva as a non-invasively-obtained specimen for molecular detection of SARS-CoV-2 RNA. Methods: In total, 153 patients with confirmed coronavirus disease 2019 (COVID-19) who had been admitted to the regional referral hospital or who self-isolated at home were included in this study. Nasopharyngeal swab specimens and saliva samples were collected on the same day, and were tested for SARS-CoV-2 infection using reverse transcriptase polymerase chain reaction. Results: The sensitivity and specificity of saliva samples were 81.5% and 76.4%, respectively, in cases that had been confirmed as COVID-19 using nasopharyngeal swab samples. Positive predictive values and negative predictive values were 92.3% and 54.1%, respectively. The highest detection rates were found among samples collected 4-7 days since symptom onset. Conclusion: Saliva samples showed comparable performance to nasopharyngeal swab specimens for the diagnosis of COVID-19 in adults. The performance of saliva as a diagnostic specimen for COVID-19 testing is particularly significant during the first week of symptoms.

Comparison enteral superoxide dismutase 1 IU and 5 IU from Cucumis melo L.C extract combined with gliadin as an antioxidant and anti-inflammatory in LPS-Induced sepsis model rats.

Sepsis is a major cause of death in intensive care units whose development is supported by an imbalance of oxidative stress and antioxidant. Superoxide dismutase (SOD) is a primer endogen antioxidant that prevents reactive oxygen species (ROS). Extensive studies on animals and humans have examined Cucumis melo L.C, a cantaloupe rich in SOD, and its combination with gliadin. The studies aimed to determine the effect of enteral administration of Cucumis melo L.C. gliadin (CME-gliadin) 28 days before inducing sepsis in rats. This experimental study aimed to compare four groups of male Wistar rats, including negative and positive control rats and those supplemented with SOD CME-gliadin 1 IU/day and SOD CME-gliadin 5 IU/day. All rats were given the same standard, except the supplementation for 28 days. Sepsis was induced by intraperitoneal injection of LPS 10 mg/kg. Enteral administration of SOD - gliadin extract of CME-gliadin for 28 days was used as antioxidant prophylaxis against oxidative stress due to sepsis. The results showed that enteral administration of CME-gliadin of 1 IU/day and 5 IU/day significantly increased SOD levels based on examination after 14 and 28 days. Also, it significantly decreased MDA (p < 0.001), TNF-α (p < 0.001), and lactate levels in rats induced by sepsis. However, the increase in lactate levels was above >1.64 mmol/l, indicating a high mortality rate. There was no significant difference in SOD, MDA, TNF-α, and Lactate levels between SOD 1 IU and SOD 5 IU. This descriptive data show that SOD 5 IU has a better result in MDA, TNF-α, and Lactate levels than SOD 1 IU.

Umbilical Cord-Derived Mesenchymal Stem Cells Improve TGF-ß, α-SMA and Collagen on Erectile Dysfunction in Streptozotocin-Induced Diabetic Rats.

Background: A Erectile dysfunction (ED) is one of the well-known comorbidities in males with diabetes mellitus (DM), whose pathogenesis might be induced by dysregulation of corpus cavernosum smooth muscle cells. UC-MSCs are multipotent cells that attract considerable interest due to immunoregulatory properties and might be a potential strategy to regulate and recover the functional cells and tissues, including tissue improvement in DMED. Objective: This study aims to determine the efficacy of UC-MSCs in improving the erectile function of DMED rats through analyzing the expression of TGF-ß, α-SMA, and collagen. Methods: Total number of 30 male Sprague-Dawley rats (6 to 8 weeks old) were randomly divided into four groups (negative control group, positive control group, T1 group, and T2 group). After 16 h fast, 24 rats were randomly selected and intraperitoneally injected with streptozotocin to induce DM. At 8 weeks after STZ injection, rats with DMED were identified by unresponsive erectile stimulation within 30 min. PC group received 500 µL; T1 rats treated with 500 µL PBS containing 1x106 UC-MSCs; T2 rats treated with 500 µL PBS containing 3x106 UC-MSCs. After MSCs treatment, the rats were sacrificed and the corpus cavernosum tissues were prepared for histological observations. Results: This study resulted in the administration of UC-MSCs could downregulate the expression of TGF-ß, α-SMA, and collagen leading to the improvement of DMED. Conclusion: UC-MSCs improve the expression of TGF-ß, α-SMA, and collagen on erectile dysfunction in streptozotocin-induced diabetic rats.

Rats' umbilical-cord mesenchymal stem cells ameliorate mast cells and Hsp70 on ovalbumin-induced allergic rhinitis rats.

Aim Allergic rhinitis (AR) is a heterogeneous condition that has been associated with inflammatory responses and is characterized by clinical typical symptoms of nasal itching, sneezing, watery discharge and congestion. Mesenchymal stem cells (MSCs) are multipotent stem cells that have the immunoregulatory ability by secreting various cytokines which potent as a promising therapeutic modality for allergic airway diseases, including AR. The aim of this study was to investigate the effect of rat UC-MSCs on the number of mast cells, the expression of Hsp70 indicated by the nasal symptoms allergic, particularly nasal rubbing in ovalbumininduced AR rats. Methods Fifteen male Wistar rats (6 to 8 weeks old) were randomly divided into three groups (control group, sham group, and OVA+MSCs group). OVA nasal challenge was conducted daily from day 15 to 21, and UC-MSCs (1x106 ) were administrated intraperitoneally to OVA-sensitized rats on day 21. Nasal rubbing was observed from day 22 to 28. The rats were sacrificed on day 22 and day 28. The nasal cavity tissues were prepared for histological observations. Results The administration of UC-MSCs could reduce the number of mast cells and the expression of Hsp70 leading to reduction of nasal symptoms allergic, particularly nasal rubbing. Conclusion Based on this finding, MSCs present a promising immediate curative effect to the inflammatory reaction in AR rats.

The CD4+CD25+FoxP3+ Regulatory T Cells Regulated by MSCs Suppress Plasma Cells in a Mouse Model of Allergic Rhinitis.

BACKGROUND: Allergic Rhinitis (AR) is the most common immunological disease that has been associated with inflammatory responses and is characterized by sneezing. Previous studies found that AR's allergen exposure significantly induces plasma cells and reduces regulatory T (Treg) cells, a population that contributes to control AR. Therefore, upregulating Treg expression can regulate plasma cells leading to inhibit sneezing in AR. Mesenchymal stem cells (MSCs) are multipotent stem cells that have the immunoregulatory and antiinflammation ability by secreting various cytokines including IL-10 and TGF-ß which potent as a promising therapeutic modality for allergic airway diseases, including AR. OBJECTIVE: To investigate the role of MSCs in generating CD4+, CD25+, and Foxp3+ Regulatory T cells associated with suppressing plasma cell in AR model. METHODS: In this study, fifteen male Wistar rats (6 to 8 weeks old) were randomly divided into three groups (control group, sham group, and MSCs treatment group). OVA nasal challenge was conducted daily from day 15 to 21, and MSCs (1x106) were administrated intraperitoneally to OVA-sensitized rats on day 21. Sneezing was observed from day 22 to 28. The rats were sacrificed on day 22 and day 28. The expression of CD4+ CD25+ Foxp3+ in Treg and plasma cells was analyzed by flow cytometry assay. RESULTS: This study showed that the percentage of plasma cell and sneezing times significantly decreased in MSCs treatment. This finding was aligned with the significant increase of CD4+CD25+Foxp3+ Treg level. CONCLUSION: MSCs administration suppress plasma cells population and sneezing times by up regulating Treg to control AR.

Apple Peel and Flesh Contain Pro-neurogenic Compounds.

As mammals evolved with exposure to particular diets, naturally abundant compounds may have become part of the set of environmental co-determinants that shaped brain structure and function. Here we investigated whether bioactive factors found in apples directly affect hippocampal neurogenesis in the adult mouse. We found that quercetin, the most abundant flavanol in apple peel, was anti-proliferative at high concentrations but pro-neurogenic at low concentrations. This was confirmed in vivo, with intraperitoneally delivered quercetin promoting survival and neuronal differentiation, without affecting proliferation. Using a bioassay-guided fractionation approach we also identified additional pro-neurogenic compounds in apple flesh that were not related to flavonoids. We found that 3,5-dihydroxybenzoic acid significantly increased neural precursor cell proliferation and neurogenesis. This work shows that both flavonoids and 3,5-dihydroxybenzoic acid are pro-neurogenic, not only by activating precursor cell proliferation but also by promoting cell-cycle exit, cellular survival, and neuronal differentiation.

Modulation of Interleukin-8 Production by Vitamin D Supplementation in Indonesian Patients with Diabetic Polyneuropathy: A Randomized Clinical Trial.

OBJECTIVES: We sought to assess the modulation of interleukin-8 (IL-8) production by vitamin D supplementation in Indonesian patients with diabetic polyneuropathy (DPN). METHODS: We conducted a cohort prospective, randomized, placebo-controlled, double-blind trial. This study was approved by the Local Ethical Committee and conducted from July 2018 to February 2019. We recruited 50 subjects with type 2 diabetes mellitus attending Haji Adam Malik General Hospital Medan, and divided them into two groups. The groups were treated for 10 weeks, either with placebo or vitamin D (D3) supplementation of 50 000 IU/week. They were evaluated by routine nerve conduction study (NCS) in the upper and lower limbs, and their serum vitamin 25-hydroxyvitamin D (25(OH)D) and IL-8 levels before and 10 weeks after placebo or vitamin D supplementation were measured. The role of IL-8 and vitamin D supplementation on the NCS was analyzed using linear regression. RESULTS: There was a significant difference between the mean vitamin 25(OH)D (p = 0.001) and IL-8 levels (p = 0.002) before and after vitamin D supplementation. There was no significant correlation between changes in vitamin 25(OH)D and IL-8 levels (p = 0.743). There was significant role of IL-8 on amplitude of the sensory sural nerve (p = 0.047; B = -0.009) and the nerve conduction velocity (NCV) of the motor tibial nerve (p = 0.007; B = -0.027). There was a significant role of vitamin D supplementation on NCSs. CONCLUSIONS: Higher IL-8 levels were correlated with poorer amplitude of the sensory sural nerve and the NCV of motor tibial nerves. Lower vitamin 25(OH)D levels were correlated with poorer distal latencies, amplitudes, and NCVs. There was no significant correlation between vitamin 25(OH)D and IL-8 levels. Thus, no sufficient evidence that vitamin D supplementation modulates IL-8 in Indonesian patients with DPN. Vitamin D3 improved NCSs in diabetic patients.

Combination of vitamin A and D supplementation for ischemic stroke: effects on interleukin-1ß and clinical outcome.

Aim Accumulated evidence suggests that vitamin A and D agonists can alleviate the development of atherosclerosis. Therefore, the aim of this study was to determine the effect of vitamin A and D combination supplement on interleukin-1ß (IL-1ß) and clinical outcome in ischemic stroke. Methods A single-blind, randomized controlled trial was conducted on ischemic stroke patients at Adam Malik Hospital between March 2018 to February 2019. The patients were randomized into 4 groups of the treatment consisting of supplementation using vitamin A or D only, combination of vitamin A and D, and placebo group, all given for 12 weeks. Clinical outcome was determined using the National Institute of Health Stroke Scale (NIHSS). At the time of admission and after the treatment was completed, all patients were measured for vitamin A, vitamin D, and IL-1ß serum level, and NIHSS score. Results From the total of 120 patients, in the combination group there were significant increments on both vitamin A (p=0.04) and vitamin D (p=0.01) serum level after 12 weeks of the treatment, compared to the other groups. In conjunction, IL-1ß serum level showed a significant decrement in the combination group (p<0.001). Lastly, the biggest improvement of NIHSS could be seen in the combination group, which was marked by the highest decrement of NIHSS score (p<0.001). Conclusion Administration of combination of vitamin A and D supplementation can significantly increase vitamin A and D serum level, decrease IL-1ß serum level, and ultimately improve clinical outcome in ischemic stroke patients.

Snakehead fish extract as an enhancer of vascular endothelial growth factor and nitric oxide levels in cerebral angiogenesis: an insight of stroke therapy.

Aim To assess the effect of snakehead fish extract administration in angiogenesis focusing on the level of vascular endothelial growth factor (VEGF), nitric oxide (NO) and VEGF receptor 2(R2) expression is ischemic stroke models. Methods An experimental study was conducted on 5 groups of ischemic stroke rats models: Group K- without carotid artery ligation, Group K+ with artery ligation, Group P1 with artery ligation and administration of 200 mg/day extract, Group P2 with artery ligation and 400 mg/day extract, and Group P3 with artery ligation and 800 mg/day extract. The VEGF expression and NO levels were assessed on day 3. Results Snakehead fish extract significantly increased VEGF levels along with increasing doses, in which the highest VEGF level was observed in P3 group (361.7±40.2; p<0.001). The NO level also increased along with an increasing dose of snakehead fish extract, in which the highest NO level was found in P3 group(59.43±0.88 µmol/gr; p<0.001). The VEGFR2 expression also increased significantly after snakehead extract administration along with increasing doses (p<0.001) in which administration of 800mg extract yielded the highest VEGFR2 expression compared with lower doses (17.7 vs. 15.6; p<0.001) Conclusion Snakehead fish extract administration increased angiogenesis process marked by an increased level of VEGF, NO and VEGFR2 expression in ischemic stroke rat models.

Predictive Model of Diabetic Polyneuropathy Severity Based on Vitamin D Level.

BACKGROUND: Type 2 Diabetes Mellitus is one of the most common metabolic diseases worldwide. The most common complication of DM is diabetic neuropathy (DN), especially diabetic polyneuropathy (DPN). Vitamin D plays an important role in the pathogenesis of DN, thus affecting its severity which can be assessed using nerve conduction study (NCS). AIM: This study aimed to develop a predictive model of DPN severity based on vitamin D level. METHODS: This was a prospective cohort study involving 50 subjects with DM which was conducted in Haji Adam Malik General Hospital Medan. All subjects were fulfilling inclusion criteria underwent laboratory examination to determine HbA1c and 25 (OH) D levels. Predictive variables were sex, age, duration of DM, smoking status, type and number of anti-diabetic drugs, the presence of metabolic syndrome, HbA1c and vitamin D levels. A scoring system was developed to determine a predictive model. The DPN severity was assessed using NCS and was re-evaluated after 3 months. RESULTS: Most of the subjects were female (60%), belonged to ≥ 50 years old age-group (88%), with DM duration < 5 years (56%), were non-smoker (90%), we're using one anti-diabetic drug (60%), were using insulin (50%), had metabolic syndrome (68%), had HbA1c level > 6.5% (94%), and had vitamin D level < 20 ng/ml (56%). A score of > 4 on this predictive model of DPN severity had a relative risk (RR) of 2.70. The predictive model had a sensitivity of 82.8% and specificity of 61.9%. CONCLUSION: A score of higher than 4 on this predictive model showed a 2.7 times higher risk of severe DPN. A predictive model of DPN severity based on vitamin D level had high sensitivity and specificity.

Sociological and Psychological Factors on Prohibited Substances Abuse in Rehabilitation Centre of Medan City, Indonesia.

INTRODUCTION: Prohibited substances issue and their abuse have become a scourge for people in Indonesia. This situation creates concern for every level of society since this is very influential to damage and can even eliminate generations at a later time. AIM: This study aims to determine the characteristics of age, education, psychological and social problems related to substance dependence experienced by individuals with substance disorders who undergo rehabilitation in Medan, Indonesia. METHODS: This study is a cross-sectional analytic, in which the sample of this study was individuals who underwent rehabilitation in the Rehabilitation Center in Medan City who fulfilled the inclusion and exclusion criteria. A structured interview was carried out with the MINI ICD-10 on part M. disorders related to psychoactive substances. Furthermore, to see the level of dependence, WHO ASSIST questionnaire (The Alcohol, Smoking and Substance Involvement Screening Test) was used. RESULTS: This study discovered that subjects with age above 21 years were the most dominant of the prohibited substance users group as many as 87 people (69%), Batak tribe with 73 people (57.9%), residence originating from outside the city with 70 people (55.6%), Unmarried with 87 people (70.2%), education level is medium (junior high school) with 117 people (92.9%) and work as many as 77 people (61.1%). The study also found that the most dominant number of prohibited substances users were single users of methamphetamine and a combination of two substances, each of which was 49 people (38.9%). There is no relationship between social factors and patterns of prohibited substance use. Also, the most dominant users of prohibited substances who undergo rehabilitation are those based on family and police (involuntary admission). Finally, as many as 70 people used methamphetamine require intensive intervention. CONCLUSION: This study shows that social and demographic factors are not related to the pattern of prohibited substance use.

Turmeric Extract Supplementation Reduces Tau Protein Level in Repetitive Traumatic Brain Injury Model.

BACKGROUND: Repetitive traumatic brain injury (RTBI) has gained much attention in this decade, especially in contact sports athletes and military personals. This injury is correlated with early neurodegenerative changes that are marked with the increased of tau protein. Turmeric extract (TE) is a well-known anti-inflammation and antioxidant that decreases tau protein expression in neurodegenerative disease. AIM: This study aimed to prove the effect of TE on tau protein level after RTBI. METHODS: Forty Sprague Dawley mice were divided into four groups, i.e. negative sham control group, the control group, and two treatment groups. A weight drop model was used by applying a 40-gram mass that was dropped from a 1-meter height onto the vertex of the head, with a total frequency of 12 times, divided into 4 days (day 0, 1, 3, and 7; 3 traumas on each day). TE was given to all treatment groups with 500 mg/kg BW doses once daily. The first treatment group had TE for seven days along the trauma. The second treatment group had pretreatment TE extract, given from seven days before first trauma and continued along the trauma protocol days. Tau protein level was measured on brain and serum using ELISA method. RESULTS: There was a significant reduction of tau protein level in both treatment groups compared to trauma group, either in serum or brain, but we also found significant differences regarding brain tau level between the treatment and pretreatment group. CONCLUSION: This study might provide evidence of with the role of pretreatment TE in RTBI.

p27kip1 Is Required for Functionally Relevant Adult Hippocampal Neurogenesis in Mice.

We asked whether cell-cycle associated protein p27kip1 might be involved in the transition of precursor cells to postmitotic maturation in adult hippocampal neurogenesis. p27kip1 was expressed throughout the dentate gyrus with a strong nuclear expression in early postmitotic, calretinin-positive neurons and neuronally determined progenitor cells (type-3 and some type-2b), lower or absent expression in radial glia-like precursor cells (type-1) and type-2a cells and essentially no expression in granule cells. This suggested a transitory role in late proliferative and early postmitotic phases of neurogenesis. Inconsistent with a role limited to cell cycle arrest the acute stimuli, voluntary wheel running (RUN), environmental enrichment (ENR) and kainate-induced seizures increased p27kip1 expressing cells. Sequential short-term combination of RUN and ENR yielded more p27kip1 cells than either stimulus alone, indicating an additive effect. In vitro, p27kip1 was lowly expressed by proliferating precursor cells but increased upon differentiation. In p27kip1-/- mice neurogenesis was reduced in vivo, whereas the number of proliferating cells was increased. Accordingly, the microdissected dentate gyrus of p27kip1-/- mice generated more colonies in the neurosphere assay and an increased number of larger spheres with the differentiation potential unchanged. In p27kip1-/- monolayer cultures, proliferation was increased and cell cycle genes were upregulated. In the Morris water maze p27kip1-/- mice learned the task but were specifically impaired in the reversal phase explainable by the decrease in adult neurogenesis. We conclude that p27kip1 is involved in the decisive step around cell-cycle exit and plays an important role in activity-regulated and functionally relevant adult hippocampal neurogenesis. Stem Cells 2017;35:787-799.

Lysophosphatidic Acid Receptor Is a Functional Marker of Adult Hippocampal Precursor Cells.

Here, we show that the lysophosphatidic acid receptor 1 (LPA1) is expressed by a defined population of type 1 stem cells and type 2a precursor cells in the adult mouse dentate gyrus. LPA1, in contrast to Nestin, also marks the quiescent stem cell population. Combining LPA1-GFP with EGFR and prominin-1 expression, we have enabled the prospective separation of both proliferative and non-proliferative precursor cell populations. Transcriptional profiling of the isolated proliferative precursor cells suggested immune mechanisms and cytokine signaling as molecular regulators of adult hippocampal precursor cell proliferation. In addition to LPA1 being a marker of this important stem cell population, we also show that the corresponding ligand LPA is directly involved in the regulation of adult hippocampal precursor cell proliferation and neurogenesis, an effect that can be attributed to LPA signaling via the AKT and MAPK pathways.

Systems Genetics Analysis of a Recombinant Inbred Mouse Cell Culture Panel Reveals Wnt Pathway Member Lrp6 as a Regulator of Adult Hippocampal Precursor Cell Proliferation.

In much animal research, genetic variation is rather avoided than used as a powerful tool to identify key regulatory genes in complex phenotypes. Adult hippocampal neurogenesis is one such highly complex polygenic trait, for which the understanding of the molecular basis is fragmented and incomplete, and for which novel genetic approaches are needed. In this study, we aimed at marrying the power of the BXD panel, a mouse genetic reference population, with the flexibility of a cell culture model of adult neural precursor proliferation and differentiation. We established adult-derived hippocampal precursor cell cultures from 20 strains of the BXD panel, including the parental strains C57BL/6J and DBA/2J. The rates of cell proliferation and neuronal differentiation were measured, and transcriptional profiles were obtained from proliferating cultures. Together with the published genotypes of all lines, these data allowed a novel systems genetics analysis combining quantitative trait locus analysis with transcript expression correlation at a cellular level to identify genes linked with the differences in proliferation. In a proof-of-principle analysis, we identified Lrp6, the gene encoding the coreceptor to Frizzled in the Wnt pathway, as a potential negative regulator of precursor proliferation. Overexpression and siRNA silencing confirmed the regulatory role of Lrp6. As well as adding to our knowledge of the pathway surrounding Wnt in adult hippocampal neurogenesis, this finding allows the new appreciation of a negative regulator within this system. In addition, the resource and associated methodology will allow the integration of regulatory mechanisms at a systems level.

Mussel-Inspired Polymer Carpets: Direct Photografting of Polymer Brushes on Polydopamine Nanosheets for Controlled Cell Adhesion.

2D mussel-inspired polydopamine (PDA) nanosheets are prepared and exploited as a functional surface for grafting various polymer brushes. The PDA nanosheet and its polymer-brush derivatives show lateral integrity and are robust; therefore, they can be detached from their substrates. Cell-adhesion tests show that the PDA nanosheet promotes cell growth and attachment, while a PDA-based poly(3-sulfopropyl methacrylate) carpet exhibits nonfouling behavior.