Isn't It Time for Establishing Mitochondrial Nomenclature Breaking Mitochondrial Paradigm?

In this work, we decided to initiate a discussion concerning heterogeneity of mitochondria, suggesting that it is time to build classification of mitochondria, like the one that exists for their progenitors, α-proteobacteria, proposing possible separation of mitochondrial strains and maybe species. We continue to adhere to the general line that mitochondria are friends and foes: on the one hand, they provide the cell and organism with the necessary energy and signaling molecules, and, on the other hand, participate in destruction of the cell and the organism. Current understanding that the activity of mitochondria is not only limited to energy production, but also that these alternative non-energetic functions are unique and irreplaceable in the cell, allowed us to speak about the strong subordination of the entire cellular metabolism to characteristic functional manifestations of mitochondria. Mitochondria are capable of producing not only ATP, but also iron-sulfur clusters, steroid hormones, heme, reactive oxygen and nitrogen species, participate in thermogenesis, regulate cell death, proliferation and differentiation, participate in detoxification, etc. They are a mandatory attribute of eukaryotic cells, and, so far, no eukaryotic cells performing a non-parasitic or non-symbiotic life style have been found that lack mitochondria. We believe that the structural-functional intracellular, intercellular, inter-organ, and interspecific diversity of mitochondria is large enough to provide grounds for creating a mitochondrial nomenclature. The arguments for this are given in this analytical work.

Maternal and Fetal Outcomes of Acute Leukemia in Pregnancy: A Retrospective Study of 52 Patients

Acute leukemia during pregnancy (P-AL) is a rare disease with limited data regarding the management and outcomes of mothers and fetuses. We retrospectively analyzed the characteristics, pregnancy outcomes and maternal and neonatal prognoses of 52 patients with P-AL collected from January 2013 to December 2020 in our center. Seventeen (32.7%) patients received chemotherapy during pregnancy (exposed cohort), while 35 (67.3%) received chemotherapy after abortion/delivery (nonexposed cohort). Twenty-six (50.0%) pregnancies ended with abortion, and 26 (50.0%) babies were born through spontaneous delivery or cesarean section. Seven infants (26.9%) were born in the exposed cohort, while 19 infants (73.1%) were born in the nonexposed cohort. Fetuses in the exposed cohort had lower gestational ages (P=0.030) and birth weights (P=0.049). Considering the safety of the fetus, seven patients in the exposed cohort received low-dose chemotherapy, one patient received all-trans retinoic acid (ATRA) and one patient only received corticosteroids as induction therapy. Patients received low-dose chemotherapy as induction therapy had a lower complete remission (CR) rate (P=0.041), and more patients in this group received HSCT (P=0.010) than patients received intensive chemotherapy. Patients who delayed chemotherapy in the nonexposed cohort experienced a trend toward a higher mortality rate than patients who received timely chemotherapy (P=0.191). The CR (P = 0.488), OS (P=0.655), and DFS (P=0.453) were similar between the exposed and nonexposed cohorts. Overall, the 4-year overall survival (OS) and disease-free survival (DFS) rates were estimated at 49.1% and 57.8%, respectively. All newborns were living, without deformities, or developmental and intellectual disabilities. Our study indicated that P-AL patients in the first trimester might tend to receive chemotherapy after abortion. Both the status of disease and patients’ willingness should be taken into consideration when clinicians were planning treatment strategies in the second or third trimester. Low-dose or delayed chemotherapy might decrease the efficacy of induction therapy and survival rate of patients, but HSCT could improve the prognosis.

Priming for Life: Early Life Nutrition and the Microbiota-Gut-Brain Axis

Microbes colonize the human body during the first moments of life and coexist with the host throughout the lifespan. Intestinal microbiota and their metabolites aid in the programming of important bodily systems such as the immune and the central nervous system during critical temporal windows of development, with possible structural and functional implications throughout the lifespan. These critical developmental windows perinatally (during the first 1000 days) are susceptible timepoints for insults that can endure long lasting effects on the microbiota-gut-brain axis. Environmental and parental factors like host genetics, mental health, nutrition, delivery and feeding mode, exposure to antibiotics, immune activation and microbiota composition antenatally, are all factors that are able to modulate the microbiota composition of mother and infant and may thus regulate important bodily functions. Among all these factors, early life nutrition plays a pivotal role in perinatal programming and in the modulation of offspring microbiota from birth throughout lifespan. This review aims to present current data on the impact of early life nutrition and microbiota priming of important bodily systems and all the factors influencing the microbial coexistence with the host during early life development.

Pregnancy facilitates maternal liver regeneration after partial hepatectomy

Liver resection induces robust liver regrowth or regeneration to compensate for the lost tissue mass. In a clinical setting, pregnant women may need liver resection without terminating pregnancy in some cases. However, how pregnancy affects maternal liver regeneration remains elusive. We performed 70% partial hepatectomy (PH) in nonpregnant mice and gestation day 14 mice, and histologically and molecularly compared their liver regrowth during the next 4 days. We found that compared with the nonpregnant state, pregnancy altered the molecular programs driving hepatocyte replication, indicated by enhanced activities of epidermal growth factor receptor and STAT5A, reduced activities of cMet and p70S6K, decreased production of IL-6, TNFα, and hepatocyte growth factor, suppressed cyclin D1 expression, increased cyclin A1 expression, and early activated cyclin A2 expression. As a result, pregnancy allowed the remnant hepatocytes to enter the cell cycle at least 12 h earlier, increased hepatic fat accumulation, and enhanced hepatocyte mitosis. Consequently, pregnancy ameliorated maternal liver regeneration following PH. In addition, a report showed that maternal liver regrowth after PH is driven mainly by hepatocyte hypertrophy rather than hyperplasia during the second half of gestation in young adult mice. In contrast, we demonstrate that maternal liver relies mainly on hepatocyte hyperplasia instead of hypertrophy to restore the lost mass after PH. Overall, we demonstrate that pregnancy facilitates maternal liver regeneration likely via triggering an early onset of hepatocyte replication, accumulating excessive liver fat, and promoting hepatocyte mitosis. The results from our current studies enable us to gain more insights into how maternal liver regeneration progresses during gestation.NEW & NOTEWORTHY We demonstrate that pregnancy may generate positive effects on maternal liver regeneration following partial hepatectomy, which are manifested by early entry of the cell cycle of remnant hepatocytes, increased hepatic fat accumulation, enhanced hepatocyte mitosis, and overall accelerated liver regrowth.

Circulating factors in young blood as potential therapeutic agents for age-related neurodegenerative and neurovascular diseases

Recent animal studies on heterochronic parabiosis (a technique combining the blood circulation of two animals) have revealed that young blood has a powerful rejuvenating effect on brain aging. Circulating factors, especially growth differentiation factor 11 (GDF11) and C-C motif chemokine 11 (CCL11), may play a key role in this effect, which inspires hope for novel approaches to treating age-related cerebral diseases in humans, such as neurodegenerative and neurovascular diseases. Recently, attempts have begun to translate these astonishing and exciting findings from mice to humans and from bench to bedside. However, increasing reports have shown contradictory data, questioning the capacity of these circulating factors to reverse age-related brain dysfunction. In this review, we summarize the current research on the role of young blood, as well as the circulating factors GDF11 and CCL11, in the aging brain and age-related cerebral diseases. We highlight recent controversies, discuss related challenges and provide a future outlook.

Pregnancy protects the kidney from acute ischemic injury

A complex analysis of acute kidney injury (AKI) in pregnant women shows that it is caused by the interaction of gestation-associated pathologies and beneficial signaling pathways activated by pregnancy. Studies report an increase in the regeneration of some organs during pregnancy. However, the kidney response to the injury during pregnancy has not been addressed. We investigated the mechanisms of the pregnancy influence on AKI. During pregnancy, the kidneys were shown to be more tolerant to AKI. Pregnant animals showed remarkable preservation of kidney functions after ischemia/reperfusion (I/R) indicated by the decrease of serum creatinine levels. The pregnant rats also demonstrated a significant decrease in kidney injury markers and an increase in protective markers. Two months after the I/R, group of pregnant animals had a decreased level of fibrosis in the kidney tissue. These effects are likely linked to increased cell proliferation after injury: using real-time cell proliferation monitoring we demonstrated that after ischemic injury, cells isolated from pregnant animal kidneys had higher proliferation potential vs. control animals; it was also supported by an increase of proliferation marker PCNA levels in kidneys of pregnant animals. We suggest that these effects are associated with hormonal changes in the maternal organism, since hormonal pseudopregnancy simulated effects of pregnancy.