Organoid assessment technologies.

Despite enormous advances in the generation of organoids, robust and stable protocols of organoids are still a major challenge to researchers. Research for assessing structures of organoids and the evaluations of their functions on in vitro or in vivo is often limited by precision strategies. A growing interest in assessing organoids has arisen, aimed at standardizing the process of obtaining organoids to accurately resemble human-derived tissue. The complex microenvironment of organoids, intricate cellular crosstalk, organ-specific architectures and further complicate functions urgently quest for high-through schemes. By utilizing multi-omics analysis and single-cell analysis, cell-cell interaction mechanisms can be deciphered, and their structures can be investigated in a detailed view by histological analysis. In this review, we will conclude the novel approaches to study the molecular mechanism and cell heterogeneity of organoids and discuss the histological and morphological similarity of organoids in comparison to the human body. Future perspectives on functional analysis will be developed and the organoids will become mature models.

Endothelial Stat3 activation promotes osteoarthritis development.

The mechanism of the balance between subchondral angiogenesis and articular damage within osteoarthritis (OA) progression remains a mystery. However, the lack of specific drugs leads to limited clinical treatment options for OA, frequently failing to prevent eventual joint destruction in patients. Increasing evidence suggests that subchondral bone angiogenesis precedes cartilage injury, while proliferating endothelial cells (ECs) induce abnormal bone formation. Signal transducer and activator of transcription 3 (Stat3) is triggered by multiple cytokines in the OA microenvironment. Here, we observed elevated Stat3 activation in subchondral bone H-type vessels. Endothelial Stat3 activation will lead to stronger cell proliferation, migration and angiogenesis by simulating ECs in OA. In contrast, either Stat3 activation inhibition or knockdown of Stat3 expression could relieve such alterations. More interestingly, blocking Stat3 in ECs alleviated angiogenesis-mediated osteogenic differentiation and chondrocyte lesions. Stat3 inhibitor reversed surgically induced subchondral bone H-type vessel hyperplasia in vivo, significantly downregulating vessel volume and vessel number. Due to the reduced angiogenesis, subchondral bone deterioration and cartilage loss were alleviated. Overall, our data suggest that endothelial Stat3 activation is an essential trigger for OA development. Therefore, targeted Stat3 blockade is a novel promising therapeutic regimen for OA.

Single-cell RNA sequencing in osteoarthritis.

Osteoarthritis is a progressive and heterogeneous joint disease with complex pathogenesis. The various phenotypes associated with each patient suggest that better subgrouping of tissues associated with genotypes in different phases of osteoarthritis may provide new insights into the onset and progression of the disease. Recently, single-cell RNA sequencing was used to describe osteoarthritis pathogenesis on a high-resolution view surpassing traditional technologies. Herein, this review summarizes the microstructural changes in articular cartilage, meniscus, synovium and subchondral bone that are mainly due to crosstalk amongst chondrocytes, osteoblasts, fibroblasts and endothelial cells during osteoarthritis progression. Next, we focus on the promising targets discovered by single-cell RNA sequencing and its potential applications in target drugs and tissue engineering. Additionally, the limited amount of research on the evaluation of bone-related biomaterials is reviewed. Based on the pre-clinical findings, we elaborate on the potential clinical values of single-cell RNA sequencing for the therapeutic strategies of osteoarthritis. Finally, a perspective on the future development of patient-centred medicine for osteoarthritis therapy combining other single-cell multi-omics technologies is discussed. This review will provide new insights into osteoarthritis pathogenesis on a cellular level and the field of applications of single-cell RNA sequencing in personalized therapeutics for osteoarthritis in the future.

Impact of feeding habits on the development of language-specific processing of phonemes in brain: An event-related potentials study.

Introduction: Infancy is a stage characterized by multiple brain and cognitive changes. In a short time, infants must consolidate a new brain network and develop two important properties for speech comprehension: phonemic normalization and categorical perception. Recent studies have described diet as an essential factor in normal language development, reporting that breastfed infants show an earlier brain maturity and thus a faster cognitive development. Few studies have described a long-term effect of diet on phonological perception. Methods: To explore that effect, we compared the event-related potentials (ERPs) collected during an oddball paradigm (frequent /pa/80%, deviant/ba/20%) of infants fed with breast milk (BF), cow-milk-based formula (MF), and soy-based formula (SF), which were assessed at 3, 6, 9, 12, and 24 months of age [Mean across all age groups: 127 BF infants, Mean (M) 39.6 gestation weeks; 121 MF infants, M = 39.16 gestation weeks; 116 SF infants, M = 39.16 gestation weeks]. Results: Behavioral differences between dietary groups in acoustic comprehension were observed at 24-months of age. The BF group displayed greater scores than the MF and SF groups. In phonological discrimination task, the ERPs analyses showed that SF group had an electrophysiological pattern associated with difficulties in phonological-stimulus awareness [mismatch negativity (MMN)-2 latency in frontal left regions of interest (ROI) and longer MMN-2 latency in temporal right ROI] and less brain maturity than BF and MF groups. The SF group displayed more right-lateralized brain recruitment in phonological processing at 12-months old. Discussion: We conclude that using soy-based formula in a prolonged and frequent manner might trigger a language development different from that observed in the BF or MF groups. The soy-based formula's composition might affect frontal left-brain area development, which is a nodal brain region in phonological-stimuli awareness.

Resting gamma power during the postnatal critical period for GABAergic system development is modulated by infant diet and sex.

Gamma band activity (30-50 Hz) plays an essential role in brain development and function, but neither the early postnatal development nor subject and environmental factors influencing this development have been reported. We documented the development of resting gamma power using high density EEG recordings obtained each month from postnatal month 2 to 6 in 518 healthy infants who were breast-fed (170; 85 boys), fed milk formula (186; 97 boys), or fed soy formula (162; 90 boys). Gamma power was determined for 44 sites distributed over major brain regions and analyses were adjusted for background variables relevant to neurodevelopment. The results show gamma power follows a gradually increasing function across this time period that varies in topographic magnitude and is differentially influenced by subject and environmental variables-among which gestation, head circumference, and infant diet-sex interactions figure most prominently. Relationships between gamma power and standardized measures of infant behavioral development appear to be emerging but are in flux during this time. Since this postnatal period is considered critical in the development of the GABAergic system underlying the generation of gamma activity, the observed findings may reflect organizational changes that will influence the future development of gamma-related behavioral and neurocognitive functions.

Infant Diet-Related Changes in Syllable Processing Between 4 and 5 Months: Implications for Developing Native Language Sensitivity.

Since maturational processes triggering increased attunement to native language features in early infancy are sensitive to dietary factors, infant-diet related differences in brain processing of native-language speech stimuli might indicate variations in the onset of this tuning process. We measured cortical responses (ERPs) to syllables in 4 and 5 month old infants fed breast milk, milk formula, or soy formula and found syllable discrimination (P350) and syntactic-related functions (P600) but not syllable perception (P170) varied by diet, but not gender or background measures. The results suggest breastfed and formula-fed infants differ in onset of this critical period in speech perception.

Infant diet, gender and the development of vagal tone stability during the first two years of life.

Postnatal nutrition influences neurodevelopment, but it is not known whether the development of individual differences in physiologic measures is related to variations in early postnatal diet. To address this issue we studied the stability of vagal tone (V)--an index of individual differences in parasympathetic heart rate control-by measuring resting V quarterly during infancy and again at 2 years in 146 breast-fed (BF), 143 milk formula-fed (MF), and 137 soy formula-fed (SF) infants. Stability of V across infancy was more consistently significant for BF than formula-fed infants. Stability was similar for boys and girls in BF and SF groups but was generally higher in boys than girls in the MF group. Significant stability between infancy and 2 years emerged later in SF than other groups and later in boys than girls. Stability generally peaked between 6 and 9 months-a time when postnatal vagal myelination slows and which may represent a pivotal stage in the development of V stability. These findings indicate that infant diet and gender are important modulators of the early development of autonomic state control.

Infant diet, gender and the normative development of vagal tone and heart period during the first two years of life.

Relationships between early postnatal diet and the development of cardiac regulation were studied using resting vagal tone and heart period measures obtained quarterly during infancy and at 2years in 158 breast-fed, 159 milk formula-fed, and 148 soy formula-fed infants. Both measures increased across time for all groups. Heart period was greater in boys than in girls-particularly in soy-fed infants. Higher vagal tone in girls than in boys was not strongly influenced by diet. At 1 and 2years measures differed among boys (soy-fed>breast-fed) but not among girls. Earlier slowing in breast-fed than in formula-fed infants in the rate of increase in vagal tone during infancy suggests that the timing of this developmental shift is sensitive to early infant diet. Finally, the findings do not indicate atypical development of cardiac activity in soy-fed infants that might be associated with estrogenic compounds in this formula.

Eating breakfast enhances the efficiency of neural networks engaged during mental arithmetic in school-aged children.

To determine the influence of a morning meal on complex mental functions in children (8-11 y), time-frequency analyses were applied to electroencephalographic (EEG) activity recorded while children solved simple addition problems after an overnight fast and again after having either eaten or skipped breakfast. Power of low frequency EEG activity [2 Hertz (Hz) bands in the 2-12 Hz range] was determined from recordings over frontal and parietal brain regions associated with mathematical thinking during mental calculation of correctly answered problems. Analyses were adjusted for background variables known to influence or reflect the development of mathematical skills, i.e., age and measures of math competence and math fluency. Relative to fed children, those who continued to fast showed greater power increases in upper theta (6-8 Hz) and both alpha bands (8-10 Hz; 10-12 Hz) across sites. Increased theta suggests greater demands on working memory. Increased alpha may facilitate task-essential activity by suppressing non-task-essential activity. Fasting children also had greater delta (2-4 Hz) and greater lower-theta (4-6 Hz) power in left frontal recordings-indicating a region-specific emphasis on both working memory for mental calculation (theta) and activation of processes that suppress interfering activity (delta). Fed children also showed a significant increase in correct responses while children who continued to fast did not. Taken together the findings suggest that neural network activity involved in processing numerical information is functionally enhanced and performance is improved in children who have eaten breakfast, whereas greater mental effort is required for this mathematical thinking in children who skip breakfast.