Iron fine-tunes innate immune responses, including macrophage inflammation. In this review, we summarize the current understanding about the iron in dictating macrophage polarization. Mechanistically, iron orchestrates macrophage polarization through several aspects, including cellular signaling, cellular metabolism, and epigenetic regulation. Therefore, iron modulates the development and progression of multiple macrophage-associated diseases, such as cancer, atherosclerosis, and liver diseases. Collectively, this review highlights the crucial role of iron for macrophage polarization, and indicates the potential application of iron supplementation as an adjuvant therapy in different inflammatory disorders relative to the balance of macrophage polarization.

Background: With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis (L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen. Tapioca starch (TS), corn starch (CS), and pea starch (PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44, respectively, were used as their dietary starch sources for 40 days. Results: Results showed that the PS diet significantly increased (P < 0.05) the final body weight, average daily gain, loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased (P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased (P < 0.05) the pH_{45 min}, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased (P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased (P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid (PUFA) in the L. thoracis compared with TS diet, but decreased (P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated (P < 0.05) the lipogenic genes (FAS, LPL, SCD, ACCα) and myosin heavy-chain (MyHC)-IIa mRNA expression levels compared with the TS diet, but downregulated (P < 0.05) the CPT1B and MyHC-IIb mRNA levels. Conclusions: In conclusion, these results provided compelling evidence that the different dietary starch source altered the carcass traits, meat flavor and quality in finishing pigs, and consumption of a diet with higher amylose/amylopectin ratio results in the production of a healthy, higher quality, and nutritional value pork.

Consumer demand for tasty and quality meat has been quickly increasing. This study investigated how dietary supplemented rutin affects meat quality, muscle fatty acid profile, and antioxidant capacity in the Chinese indigenous Qingyuan partridge chicken. A cohort of 180 healthy 119-day-old chickens was subjected to a randomized assignment into three groups, identified as the control, R200, and R400 groups, with respective supplementation of 0, 200, and 400 mg/kg of rutin. The results revealed insignificance in growth performance, namely, average daily gain, average daily feed intake, and feed-to-gain ratio, across the various treatment groups (p > 0.05). Nevertheless, dietary rutin supplementation increased (p < 0.05) breast muscle yield and intramuscular fat content in breast muscle and decreased (p < 0.05) drip loss in breast muscle. Rutin supplementation increased (p < 0.05) the content of high-density lipoprotein but decreased (p < 0.05) the contents of glucose, triglyceride, and total cholesterol in serum. Rutin supplementation increased (p < 0.05) the levels of DHA (C22:6n-3), total polyunsaturated fatty acids (PUFAs), n-3 PUFAs, decanoic acid (C10:0), the activity of Δ5 + Δ6 (22:6 (n − 3)/18:3 (n − 3)), and the ratio of PUFA/SFA in breast muscle but decreased (p < 0.05) the level of palmitoleic acid (C16:1n-7), the ratio of n-6/n-3 PUFAs, and the activity of Δ9 (16:1 (n − 7)/16:0). Rutin treatment also reduced (p < 0.05) the contents of malondialdehyde in serum and breast muscle, and increased (p < 0.05) the catalase activity and total antioxidant capacity in serum and breast muscle and the activity of total superoxide dismutase in serum. Additionally, rutin supplementation downregulated the expression of AMPKα and upregulated the expression of PPARG, FADS1, FAS, ELOVL7, NRF2, and CAT in breast muscle (p < 0.05). Convincingly, the results revealed that rutin supplementation improved meat quality, fatty acid profiles, especially n-3 PUFAs, and the antioxidant capacity of Qingyuan partridge chickens.

The accumulation of reactive oxygen species (ROS) triggers oxidative stress in cells by oxidizing and modifying various cellular components, preventing them from performing their inherent functions, ultimately leading to apoptosis and autophagy. Glutathione (GSH) is a ubiquitous intracellular peptide with multiple functions. In this study, a hydrogen peroxide (H${}_2$O${}_2$)-induced oxidative damage model in IPEC-J2 cells was used to investigate the cellular protection mechanism of exogenous GSH against oxidative stress. The results showed that GSH supplement improved the cell viability reduced by H${}_2$O${}_2$-induced oxidative damage model in IPEC-J2 cells in a dose-dependent manner. Moreover, supplement with GSH also attenuated the H${}_2$O${}_2$-induced MMP loss, and effectively decreased the H${}_2$O${}_2$-induced mitochondrial dysfunction by increasing the content of mtDNA and upregulating the expression TFAM. Exogenous GSH treatment significantly decreased the ROS and MDA levels, improved SOD activity in H${}_2$O${}_2$-treated cells and reduced H${}_2$O${}_2$-induced early apoptosis in IPEC-J2 cells. This study showed that exogenous GSH can protect IPEC-J2 cells against apoptosis induced by oxidative stress through mitochondrial mechanisms.

The carbon footprint of pork production is a pressing concern due to the industry’s significant greenhouse gas emissions. It is crucial to achieve low-carbon development and carbon neutrality in pork production. Thus, this paper reviewed the recent studies about various sources of carbon emissions throughout the current pork production chain; feed production, processing, and manure management are the major sources of carbon emissions. The carbon footprint of the pork production chain varies from 0.6 to 6.75 kg CO₂e·kg⁻¹ pig live weight, and the carbon footprint of 1 kg of pork cuts is equivalent to 2.25 to 4.52 kg CO₂e. A large reduction in carbon emissions could be achieved simultaneously if combining strategies of reducing transportation distances, optimizing farmland management, minimizing chemical fertilizer usage, promoting organic farming, increasing renewable energy adoption, and improving production efficiency. In summary, these mitigation strategies could effectively decrease carbon emissions by 6.5% to 50% in each sector. Therefore, a proper combination of mitigation strategies is essential to alleviate greenhouse gas emissions without sacrificing pork supply.

Introduction: The reasonable and efficient utilization of agricultural by-products as animal feed has the capacity to not only mitigate the scarcity of conventional feedstuff but also alleviate the environmental load. This study was aimed to investigate the effects of feeding citrus pomace (CP) fermented with combined probiotics on growth performance, carcass traits, meat quality and antioxidant capacity in yellow-feathered broilers.Methods: A cohort of 540 female yellow-feathered broilers (Qingyuan partridge chicken, 90-day-old) were randomly divided into three groups and, respectively, fed the basal diet (Control), diet containing 10% unfermented CP (UFCP) and diet containing 10% fermented CP (FCP).Results: The results showed that dietary FCP significantly increased (p < 0.05) the final-body-weight and average-daily-gain of broilers, and the pH_{45 min} and b*_{24 h} values in breast muscle, while tendentiously lowering the feed-to-gain ratio (p = 0.076). The levels of inosine monophosphate (p < 0.05) and intramuscular fat (p = 0.083) in the FCP group were higher than those in the control group. Remarkably, dietary FCP and UFCP increased the levels of polyunsaturated fatty acids (PUFAs) and n-6 PUFAs (p < 0.05). Moreover, dietary FCP decreased (p < 0.05) the malondialdehyde content and increased (p < 0.05) the glutathione peroxidase content in serum. Ingestion of FCP and UFCP increased the levels of total antioxidant capacity and catalase activity in serum, and concentrations of glutathione peroxidase and catalase in breast muscle (p < 0.05). Additionally, diet containing FCP or UFCP upregulated the expression of SREBP − 1c, FAS, NRF2, GSH-Px, and CAT in breast muscle (p < 0.05).Discussion: Overall, dietary supplementation with FCP obviously improved meat quality, enhanced the antioxidant capacity and regulated the lipid metabolism, contributing to the improvement of growth performance of yellow-feathered broilers.